AI Image Detector (Check Fake AI Photos)

Check if an image was generated by AI. Detects OpenAI (DALL-E / ChatGPT), Midjourney, Stable Diffusion provenance signals, and real camera hardware metadata.

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Binary, Decimal & Hex Base Converter

Convert numbers between Decimal, Binary, Hex, and Octal. Features instant bidirectional sync, friendly presets, and BigInt precision.

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Docker Run to Docker Compose yml Converter

Convert complex docker run commands into standard docker-compose.yml files. Parses ports, volumes, environment variables, and restart policies.

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Keyboard KeyCode & NKRO Rollover Tester

Test keyboard keys, anti-ghosting rollover (NKRO), and chatter online in your browser. Live keymap highlights pressed keys with mechanical audio.

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JSON to TypeScript Interface & Type Generator

Convert JSON objects into clean TypeScript interfaces or type aliases. Automatically infers nested objects, array element types, and optional properties.

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Network Port Numbers & Service Lookup

Search port numbers or service names to look up TCP/UDP protocols, standard software daemons, and security notes instantly.

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Git Interactive Cheatsheet (Scenario Generator)

Search your scenario (e.g. 'undo commit', 'force overwrite') to generate exact copy-ready Git terminal commands with safety warnings.

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SVG to React / Vue JSX Component Converter

Transform raw SVG vector markup into clean React JSX/TSX or Vue 3 component code. Automatically camelCases attributes and injects props.

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JSON Formatter & Validator (Auto-Fix Commas)

Format, minify, sort, and repair JSON in real time. Automatically detects syntax errors with line numbers and cleans trailing commas locally.

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Bcrypt Password Hash Generator & Verifier

Generate secure Bcrypt password hashes ($2a$/$2b$) or verify matching passwords locally. Customize cost rounds and inspect salt/hash components.

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Text Line Deduplicator & Sorter

Paste multi-line text or lists to strip duplicate lines instantly with live counts. Supports alphabetical sorting, whitespace trimming, and SQL/comma formatting.

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Universal Color Converter (HEX, RGB, HSL, CMYK)

Real-time bidirectional conversion between HEX, RGB, HSL, HSV, print CMYK, and CSS color variables. Includes tints, shades, and harmonies.

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HAR File Viewer & Network Waterfall

Inspect requests, headers, and waterfall timings locally from .har files.

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SSL & X.509 Certificate Decoder

Decode and inspect X.509 SSL/TLS certificates locally. View Subject, Issuer, Validity expiration countdown, SANs, and SHA-256 fingerprints.

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RSA & ECC Keypair Generator

Generate RSA/ECC key pairs in your browser. Private keys are never uploaded.

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JWT Signer & Signature Verifier

Sign and verify HS256 JWTs locally using the browser's Web Crypto API.

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JWT Token Decoder & Claims Viewer

Inspect token header and payload to troubleshoot authentication issues.

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Nginx Reverse Proxy Config Builder

Draft Nginx reverse proxy configs with WebSocket, SSL redirect, and gzip.

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robots.txt Builder & Crawler Simulator

Build robots.txt rules and test whether specific URL paths are allowed or blocked.

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.htaccess to Nginx Rewrite Converter

Translate common Apache rewrite rules into an Nginx config draft.

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Live DNS Records Lookup (DoH)

Look up common DNS records through a selected public DNS-over-HTTPS resolver.

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HTTP Security Headers Inspector

Inspect security response headers when the target permits browser CORS access, with clear limitations.

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My Public IP & ISP Location Lookup

What's my IP? Your public address, plus city, region, ISP and timezone — detected automatically, nothing stored by us.

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IP Subnet Mask & CIDR Calculator

Network, broadcast, usable hosts and wildcard — plus how many IPs your cloud provider actually lets you use.

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Audio Cutter & MP3 Trimmer

Cut, trim, and split MP3, WAV, AAC, and audio files locally in your browser with interactive waveforms and millisecond precision.

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SVG Optimizer & Code Minifier

Strip editor metadata, clean empty tags, and reduce coordinate precision to optimize SVG files locally.

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SVG to PNG & JPEG Image Converter

Render SVG files or markup to PNG, JPEG, or WebP at custom scales (1x to 8x) locally in your browser.

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Image Compressor to Target File Size

Compress toward a requested KB target with local Canvas binary search — no uploads.

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Image Grid Splitter & Sticker Slicer (Export ZIP)

Slice multi-tile images, sticker packs, and 9-grid photos into individual images. Supports 4x4 (16 tiles), 3x3 (9 tiles), custom grids, border padding trim, and bulk ZIP download.

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Image & Circular Avatar Cropper (Transparent)

Crop photos and avatars effortlessly in your browser. Supports 1:1 squares, circular transparent masks, 16:9 banners, zoom, rotation, and local export.

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Favicon.ico & Apple Touch Icon Maker

Create multi-size favicon.ico, Apple Touch icons, and HTML snippet from one image.

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Photo EXIF & GPS Location Inspector

Inspect camera settings, shutter speed, aperture, ISO, lens details, and exact GPS coordinates from your photos locally.

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Photo EXIF & Privacy Stripper

Re-encode an image locally with Canvas to remove common EXIF metadata.

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Batch Image Dimensions & Aspect Ratio

Read dimensions, aspect ratios, types, and sizes for multiple images locally.

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Image Color Palette Extractor

Extract dominant colors from an image and copy the palette as HEX, RGB, CSS, or JSON.

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Image Steganography (Hide Text in Image)

Hide or extract UTF-8 text in PNG pixels locally, with capacity checks and optional password obfuscation.

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Photo Contact Sheet & Grid Maker

Arrange multiple images into a labeled contact sheet and download it as one image.

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CSS Layered Smooth Shadow Generator

Set color, offset, and blur to create layered, soft CSS drop shadows.

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Text & Background Contrast Checker

Test foreground and background color combinations against WCAG 2.1 AA and AAA standards with real-time ratio, compliance status, and live typography preview.

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Aspect Ratio & Screen Scaling Calculator

Calculate proportional dimensions, simplify video and image resolutions into standard ratios (16:9, 4:3, 9:16), scale sizes, and compute screen PPI.

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JSON Semantic Diff & RFC 6902 Patch

Compare two JSON documents semantically offline. Normalizes key orders, highlights changes, and generates RFC 6902 JSON Patch.

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CSV to JSON & JSON to CSV Converter

Convert CSV to JSON and JSON to CSV locally with smart type inference (numbers, booleans, nulls), custom delimiters, and RFC 4180 quote escaping.

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HTML to Markdown & MD to HTML

Turn HTML markup into clean, portable Markdown preserving core structure.

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File to Base64 & Data URI Converter

Encode any file (images, fonts, PDFs, archives) into standard Base64 / Data URI, or reconstruct binary files from Base64 text.

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SQL to JSON & Bulk Insert Generator

Convert SQL INSERT statements to clean JSON arrays and JSON to bulk SQL INSERT statements offline. Handles quotes, numbers, and nulls.

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Social Share Card & OpenGraph Preview

Preview social cards and check titles, descriptions, and images before posting.

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Cron Expression Visual Builder

Visually generate standard 5-part Linux Crontab and 6-part Spring / Quartz cron expressions with live execution preview.

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Cron Expression Explainer & Next Runs

Understand any cron schedule in plain English and see exactly when it will run next.

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Regex Tester with Live Match Highlights

Test a regular expression against sample text and inspect matches and capture groups locally.

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Regex Token-by-Token Explainer

Found a regex you don't understand? Paste it and get a token-by-token plain-English explanation — no more squinting at <code>\d{2,4}[a-z]?</code>.

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SQL Formatter & Beautifier Online

Paste mangled SQL, get readable SQL. Keywords capitalized, clauses on their own lines, parentheses indented — all locally in your browser.

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Run SQL Queries on CSV in Browser

Load a CSV into local SQLite and run safe SELECT queries directly in your browser.

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JSONPath Query & Node Extractor

Query JSON with keys, array indexes, wildcards, and recursive key lookup locally.

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JSON Schema Validator (Draft 7)

Validate JSON against a practical local JSON Schema subset with readable path-level errors.

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JSON Flattener to Dot Notation

Nested JSON is great for APIs, terrible for spreadsheets. Flatten it into <code>user.address.city</code> style keys — ready for CSV, logs and quick analysis.

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JSONL (JSON Lines) Validator & Converter

Validate JSON Lines with exact error lines, convert to/from JSON arrays, and inspect the schema of your dataset — no upload, all in your browser.

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Markdown Live Preview Editor & Exporter

Write Markdown with a live preview and export-ready HTML, entirely in your browser.

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Visual Markdown Table Generator

Visual Markdown Table Generator. Edit rows and columns in a simple grid, set alignment per column, and copy a ready-to-paste Markdown table — or import an existing table to tweak it.

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Markdown Table of Contents (TOC) Builder

Generate a Markdown table of contents with stable heading anchors locally.

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Text & Code Diff Checker Side-by-Side

Paste the original and the changed version — see exactly what's added, removed and unchanged. Word-level diff, side-by-side, in your browser.

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cURL to Python, JS, Go Code Converter

Copied a cURL command from browser devtools or an API doc? Paste it here and get instant Python, JavaScript, Go or PHP code — ready to run, no manual translation.

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Swagger & OpenAPI Spec Viewer

Got an openapi.json from a colleague and no Swagger UI handy? Paste it — get every endpoint in a readable table with methods, summaries and parameter counts.

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In-Browser ZIP File Creator

Pack multiple local files into one ZIP archive in your browser.

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In-Browser ZIP Extractor & Preview

Inspect a ZIP archive locally and download individual entries without server upload.

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PDF Watermark Tool (Private & In-Browser)

Add visible text watermarks to mark document provenance.

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All-in-One PDF Utility Suite

Merge, split, extract, delete, rotate, and reorder PDF pages entirely in your browser.

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PDF Text Diff & Comparator

Compare two PDFs by SHA-256, page count, and extractable text without uploading them.

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Merge Multiple PDF Files Online

Combine multiple PDF files locally in a chosen order.

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Split PDF into Page Ranges

Split one PDF into separate files using page ranges.

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Extract Specific Pages from PDF

Extract selected page ranges into a new PDF locally.

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Reorder, Rotate & Delete PDF Pages

Reorder, rotate, or delete pages from a PDF.

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Convert PDF Pages to PNG & JPG Images

Export every page, or selected pages, as PNG or JPEG images.

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Combine Images to Single PDF Document

Turn multiple PNG, JPEG, or WebP images into one PDF locally.

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Convert Plain Text to Formatted PDF

Turn plain text or Markdown notes into a downloadable PDF in your browser.

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Extract Readable Text from PDF Online

Extract selectable text from a PDF locally in your browser and copy or download it as TXT.

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View & Sanitize PDF Document Metadata

Inspect and remove standard PDF metadata locally without changing the original file.

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Recipe Scaler (Double, Half or Scale by Servings)

Scale a recipe by servings or multiplier and calculate ingredient amounts.

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Pet Daily Food Portions & 7-Day Transition

The bag says "feed 2–3 cups" — useless. Enter your dog's weight and activity and get a science-based daily amount in calories, cups and grams, tuned to your food's density.

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College Study Hours & Credit Load Planner

The old rule: for every credit hour, plan 2–3 hours of study. Enter your course load and weekly budget and get a realistic per-course plan — plus a sanity check on whether you're overcommitted.

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Class Average & Grade Distribution

Paste the whole class's scores and get the full picture: mean, median, range, distribution buckets — and a data-driven hint about whether the test needs a curve.

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Leftovers & Food Shelf Life Guide

Look up recommended pantry, fridge, and freezer storage times for common foods.

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User-Agent Parser & Device Inspector

Who's hitting your site? Paste a UA string (or a batch, one per line) and get browser, version, OS, device type and bot detection — locally, no tracking.

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Email Header Analyzer & Sender IP Tracer

Got a suspicious email or a deliverability problem? Paste the raw headers (the "Show original" output) and get a clean breakdown: sender, routing chain, and SPF/DKIM/DMARC verdicts.

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SemVer Version Comparator & Range Tester

Which version is newer? Does <code>^2.3.1</code> accept <code>2.9.0</code>? Paste your versions and ranges — get the answer and a plain-language breakdown of the rules.

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Snowflake ID Timestamp Decoder

Discord user IDs, tweet IDs, Instagram post IDs — they're all snowflakes with a timestamp baked in. Paste one or a batch, get the exact creation time.

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Zero-Width Character Remover (ZWSP)

Text looks fine but fails validation? AI output, scraped pages and copied code are full of invisible characters — zero-width spaces, BOMs, soft hyphens. Paste it here, see every one highlighted, and strip them in one click.

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Gzip vs Brotli Compression Benchmark

Wondering if Brotli is worth enabling? Paste your real payload — HTML, JS, JSON — and measure gzip vs deflate right here. Brotli isn't available in browsers, so you get its typical ratios as an reference band.

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Party Food & Meat Portions Calculator

Estimate portion quantities before shopping — and stop buying twice what people eat. Enter guests, pick a menu style, get exact purchase amounts for meat, sides and dessert.

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Spaced Repetition Review Schedule

Spaced repetition review schedule. Enter your exam date, get a review plan that spaces your sessions at the intervals memory science actually supports — 1, 3, 7, 14, 30 days.

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Classroom & Exam Seating Chart Maker

Quickly generate printable seating charts: paste the roster, pick a grid, shuffle — or sort alphabetically — and print. No accounts, no ads, nothing leaves your browser.

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Meat & Poultry Roast Time and Safe Temps

Roast times per pound for beef, pork, lamb and chicken — with target internal temperatures, rest time guidance, and a cooking clock counted back from dinner.

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Solution Dilution Calculator (C1V1 = C2V2)

Calculate dilution parameters from known concentrations, volumes, and target conditions.

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English to IPA Phonetic Transcriber

Need the phonetic spelling for a word you're teaching or learning? Common words come straight from a curated dictionary (US/UK); everything else gets a transparent rule-based estimate — clearly marked.

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TOML to JSON & JSON to TOML Converter

Cargo.toml, pyproject.toml, Caddyfile-adjacent configs — TOML is everywhere in the modern toolchain, but every API wants JSON. Convert both ways, locally, instantly.

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Git Commit Message Builder

Consistent Conventional Commits without memorising the format — pick a type, add scope and description, get a copy-ready message with body and footer.

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CSS Specificity Calculator (Debug Style Overrides)

Why isn't my rule applying? Paste your selectors — one per line — and see their (a,b,c) weights ranked, with a breakdown of what counted.

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ULID Generator & Timestamp Decoder

ULIDs look like UUIDs but sort by time — great for database keys and logs. Generate one, decode a timestamp from an existing ID, or batch a hundred.

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LED Bulb Annual Electricity Savings Calculator

Comparing incandescent vs. LED operating costs. See the real yearly cost of your current bulbs vs LEDs — and exactly when the upgrade pays for itself.

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Chemical Reaction Percent Yield Calculator

Lab report due? Percent yield is actual ÷ theoretical × 100. Enter any two values and get the third — plus an plain-language interpretation of what your yield means.

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Chemical Equation Balancer & Stoichiometry

2 H₂ + O₂ → 2 H₂O: if I burn 4 g of hydrogen, how much water comes out? Enter the equation's species with coefficients and molar masses, then any known amount — get every other amount in moles and grams.

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Jet Lag & Sleep Adjustment Schedule

Flying to Tokyo from New York (14 hours) vs. London to New York (5 hours) — very different recoveries. Get your adjustment timeline and a light-and-sleep game plan.

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Sleep Debt & Recovery Days Calculator

Estimate accumulated sleep debt and view a sensible catch-up schedule.

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Seed Starting & Spring Planting Calendar

Tomatoes inside 6–8 weeks before the last frost; beans go straight in the ground after. Enter your last frost date and get a full sowing calendar for 15+ crops.

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Appliance Wattage & Monthly Electricity Cost

That space heater and the old fridge are quietly eating your bill. Enter watts, hours and your rate — see every appliance's true yearly cost.

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Email Spam Score & Trigger Words Checker

"You've won a prize" with a weird sender? Paste the email (sender, subject, body) and get a transparent 0–100 spam score with every reason listed — no AI black box, no data uploaded.

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HTML/CSS/JS Sandboxed Live Runner

Testing an email template or a button style? Paste your HTML (CSS + JS included), watch it render live — nothing is uploaded, the preview runs in a sandboxed iframe.

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CSV & Spreadsheet to Markdown Table

Convert spreadsheet data to Markdown. Paste CSV, Excel export or tab-separated data, and get a clean Markdown table for GitHub, Notion or any docs site — with the reverse direction built in.

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Random Team & Group Generator

Project teams, lab pairs, classroom groups — paste names, pick a method, shuffle. Optional exclusions keep known troublemakers apart (or best friends together).

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YAML to JSON Converter & Formatter

Validate YAML indentation, detect syntax errors, and convert to JSON.

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Days Between Dates & Countdown Calculator

"How many days until the deadline?" "How many workdays between these dates?" Pick two dates — get the full breakdown, including business days and a quick add-days mode.

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Exact Age & Days Lived Calculator

Not just "26" — your exact age in years, months and days, plus days until the next birthday. Forms, visas and birthday plans all covered.

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Base64 Text & URL-Safe Encoder/Decoder

Encoding text as base64 for auth headers, data URIs or JWT segments? Encode, decode, and switch to URL-safe — all locally, Unicode included.

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UUID v4 & GUID Batch Generator

Need a unique ID? v4 for pure randomness, v7 if you want time-sortable database keys. Generate one or a batch — and decode the timestamp hidden in any v1/v6/v7.

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URL Slug Generator (Clean & SEO Friendly)

"My Awesome Blog Post!! (2026 Edition)" → <code>my-awesome-blog-post-2026-edition</code>. Paste any title, get a clean URL slug — with options for separators and length.

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Word Counter & Spoken Speech Duration

Essay hitting the 500-word limit? Blog post needs 1,500? Paste or type — see words, characters, sentences, reading time and keyword frequency, live.

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Text Case Converter (camelCase, snake_case)

ALL CAPS where it should be Title Case? Convert any text between the seven useful cases — instantly, with copy buttons on every result.

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Working Business Days Calculator (Skip Weekends)

"Deliver in 10 working days" — which date is that? Or "how many business days until payroll?" Count workdays between dates, or add N working days to any date.

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Oven to Air Fryer Temp & Time Converter

Convert conventional oven recipes to air fryer settings to air fryer temperature & time — or the other way around.

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Batch Unix Epoch Timestamp Converter

Convert entire lists of Unix timestamps to readable dates — or back. No limits, nothing to install.

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Percentage to GPA 4.0 Scale Converter

Convert percentage grades to a 4.0 GPA scale — single grade or a full transcript with credits.

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Oven to Slow Cooker Recipe Time Converter

Convert oven recipes to slow cooker settings into slow cooker (Crockpot) settings — time ranges for both Low and High, with liquid and safety guidance.

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Pasta Serving Size per Person (Dry & Fresh)

Never guess again: how much dry pasta per person, with cooked weight, water and sauce amounts for any number of guests.

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HTTP Status Codes & Debugging Cheat Sheet

Every status code, explained in plain English — with what it means, when you'll see it, and how to fix the ones that hurt.

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Sourdough Total Hydration & Baker's Percentage

Total dough hydration including your starter — at any starter hydration — plus baker's percentages, or work backwards from a target hydration.

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Class Attendance & Max Missable Classes

Your attendance percentage right now — plus the question everyone actually asks: how many more classes can I miss?

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Target GPA Required Grade Calculator

Wondering if that 3.2 can become a 3.5 before graduation? Enter your numbers and find out exactly what it takes — or if it's already impossible.

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Wall Paint Gallons & Liters Calculator

Brand-neutral, no sign-up, no store. Room dimensions in, gallons out — with doors and windows deducted automatically.

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Party Drink & Alcohol Planner

Guests, hours, and a bar style — out comes the full shopping list: bottles, cases, mixers, non-alcoholics and ice.

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Teacher EZ Grader Score & Missed Questions Chart

The classic grading wheel, rebuilt for your phone. Type questions and wrong answers — get the score instantly, or grade a whole stack at once.

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Coffee Brew Ratio Calculator

Great coffee is simple math. Tell it how much coffee you want to brew, pick your ratio, and get exact grams and cups of water — plus the reverse: how much coffee for a given water amount.

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Caffeine Bedtime Half-Life & Sleep Disruption Tracker

Estimate caffeine clearance over time to help plan around sleep.

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Video Bitrate & File Size Calculator

Calculate video bitrate, size, or duration: bitrate × duration = file size. Pick any two, get the third — with platform presets and quality sanity checks.

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SD Card Dashcam & CCTV Recording Time

128 GB, 4K at 100 Mbps — how long can you actually record? Pick your camera or type your bitrate.

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AI Chat Export Viewer

Your ChatGPT, Claude or Gemini export contains everything you've ever asked an AI — but the official export is a wall of JSON. Drop the file here and browse it like a normal app. Nothing is uploaded.

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Linux chmod 755/644 Permissions Calculator

Toggle read, write, and execute bits to convert between octal and symbolic chmod.

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URL Parser & Query String Decoder

Paste a URL and see every piece — scheme, host, port, path, each query parameter, and the fragment. Great for debugging redirects, reading API links, or untangling a long share URL.

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Lorem Ipsum Dummy Text (Latin & Chinese)

Generate dummy filler text for design mockups, prototypes, and typesetting. Supports Latin Lorem Ipsum and Chinese placeholder text.

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HTML Entities Encoder & Decoder

Convert special characters to and from HTML entity representations. Supports named, decimal, and hexadecimal entities to prevent XSS and rendering bugs.

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URL Encoder & Decoder Online

Encode and decode URLs and query strings to and from UTF-8 percent-encoding. Supports encodeURIComponent, encodeURI, and RFC 3986.

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.gitignore File Generator by Tech Stack

Select your stack and get a ready-to-paste <code>.gitignore</code>. Covers Node, Python, Java, Go, Rust, .NET and the usual OS/editor cruft — so you never commit <code>node_modules</code> by accident again.

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World Timezone Converter & Meeting Planner

"Meeting at 10 AM PT — what time is that for me?" Or "If my flight lands at 14:30 JST, when should I pick up at Narita?" Pick a time and see it across any timezone, with DST handled automatically.

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Mock Data & Fake User Profile Generator

Generate realistic fake data for testing, demos and prototypes — names, emails, cities, dates, numbers and more. Output as JSON or CSV, however many rows you need.

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Password Generator

Generate strong passwords with customizable length, character types — uppercase, lowercase, numbers, symbols. Check password strength in real-time.

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Compound Interest & Monthly Investment Calculator

See how your money grows when your returns earn returns. Adjust the sliders below to model any investment scenario — with regular contributions and daily-to-yearly compounding.

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Online Hash Generator (MD5, SHA-256)

Generate MD5, SHA-1, SHA-256, SHA-512 hashes of any text, plus HMAC with a secret key. Client-side only — your data never leaves the browser.

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Mortgage Monthly Payment & Amortization Calculator

Estimate monthly mortgage payments: loan amount, interest rate, term, property tax, insurance and PMI. See the amortization schedule and total cost of the loan — all in your browser, nothing leaves the page.

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Reaction Time Test (Visual Reflex Benchmark)

Test your visual reflex speed in milliseconds. Click as fast as you can when the red screen turns green across 5 rounds to benchmark against gamers.

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CPS Test (Clicks Per Second)

Click as fast as you can inside the click zone! Test your max CPS across 1s, 5s, 10s, or 30s intervals to benchmark your clicking stamina.

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Minimalist Pomodoro Timer (25m Focus & Chime)

A distraction-free Pomodoro focus timer with 25-minute work and 5-minute break cycles. Features soothing chimes and tab countdown.

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BMI & Ideal Healthy Weight Range Calculator

Your Body Mass Index in one look — plus the healthy weight range for your height and where you sit on the scale. Metric or imperial, all computed locally.

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TDEE & Weight Loss Calorie Deficit Calculator

Total Daily Energy Expenditure — the calories you burn in a day. Get your maintenance number, plus cut and bulk targets with a macro split. Estimate only; adjust with real-world results.

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Daily Water Intake Calculator (Avoid Dehydration)

How much water should you actually drink? Start from your body weight, then add for activity, heat, and pregnancy. Liters, ounces, and bottles — plus a schedule that fits a normal day.

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Body Fat Percentage Calculator (US Navy Tape Method)

The US Navy circumference method — a few tape measurements and your height, no calipers needed. Estimate body fat percentage, category and lean mass.

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Dog & Cat to Human Age Converter (By Breed Size)

The old "1 dog year = 7 human years" is wrong — dogs age fast early, then slow down. Use the veterinary formula that accounts for size, and see the life-stage milestones.

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Savings Goal Timeline Planner

Vacation, car, emergency fund, a console — whatever it is, here's the monthly number. With interest on your side, or a timeline that tells you when you'll get there.

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Workout Calorie Burn Calculator (MET Values)

Calories burned = MET × weight × hours. Pick an activity, enter your weight and time — get a solid estimate based on the Compendium of Physical Activities.

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Roman Numeral to Arabic Number Converter

1999 → MCMXCIX, or MMXXIV → 2024. Convert either direction, with validation and the classic subtractive rule handled for you.

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Celsius & Fahrenheit Temperature Converter

Celsius, Fahrenheit, Kelvin — enter any value in any unit and see all three instantly, with the formula that got you there.

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Universal Unit Converter (Length, Weight, Area, Volume)

Kilometers to miles, kg to pounds, liters to gallons, °C to °F, Mbps to GB — one box for the everyday conversions you keep Googling.

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Fuel Cost Calculator

Road trip both ways? Daily commute? Enter distance, your car's consumption and the fuel price — get the exact cost, plus round-trip and monthly estimates.

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Running Pace & Marathon Finish Time Calculator

Set any two of pace, distance and time — get the third. Check your 5K goal pace, or what your last run's splits really mean.

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50/30/20 Monthly Budget Planner

Split monthly income into 50/30/20 starting allocations for needs, wants, and savings.

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One Rep Max 1RM Calculator (Bench, Squat, Deadlift)

Lifted 80 kg for 5? Your estimated 1RM is ~92 kg. Get the number, then see the weight for every training zone — power, strength, hypertrophy, endurance.

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TV & Projector Screen Dimensions Calculator (65, 75, 100)

Buying a TV? A 65" is 57" wide — will it fit the cabinet? Enter the diagonal, get width & height, plus the right viewing distance for your content.

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International Shoe Size Converter (US, EU, UK, CM)

Shopping overseas? EU 42 vs US 9 vs UK 8 — never guess again. Pick a system, enter the size, get all the others plus foot length.

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Live Foreign Currency Converter

Live exchange rates for major currencies — <b>USD, EUR, CNY, JPY, GBP, HKD…</b> Updated daily from European Central Bank reference rates. No sign-up, no tracking, runs in your browser.

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Historical Exchange Rate Lookup

How has USD/CNY moved this year? Chart any currency pair against the ECB reference rate — 1 month to 5 years, honest trends, no account.

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QR Code Generator (WiFi, URL, Text)

Generate QR codes locally in your browser — URL, text, Wi-Fi login, email, phone. Pick a color and size, download PNG. No account, no watermark, no tracking.

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Pregnancy Due Date & Week Calculator

Due date from your last period or conception date — with trimester dates and the full week-by-week timeline. Estimates only; your provider's dating scan is the authority.

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Mortgage Early Payoff & Interest Savings Calculator

Extra $100 a month on your mortgage — what's that actually worth? See how one-time or monthly extra payments shorten the loan and slash total interest.

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Ovulation & Fertile Window Tracker

Find your fertile window — the days when conception is most likely. Based on your cycle length and last period, with clear caveats about cycle variation.

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Paycheck Take-Home Pay & Tax Deductions Calculator

What's actually in your pocket? Estimate take-home pay after federal income tax, FICA, state tax and pre-tax deductions — hourly or salary, any pay frequency.

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Rent vs Buy Financial Comparison & Break-Even Timeline

"Should I keep renting or buy?" Compare the real long-term numbers: monthly costs, the equity you build, home appreciation, and the year buying finally wins.

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Sleep Cycle & Wake-Up Calculator (90-Min Sleep Rule)

Sleep runs in ~90-minute cycles. Wake up at the end of one and you feel great; wake mid-cycle and you feel terrible. Plan your bedtime or alarm accordingly.

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Source Lines of Code (SLOC) Counter

"How big is this project?" Paste code and get a tokei-style breakdown: code lines, comment lines, blank lines — with a simple language picker for comment syntax.

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Debt Payoff Calculator (Snowball vs Avalanche Method)

Snowball (smallest first) or avalanche (highest APR first)? Enter your debts and monthly budget — see both plans side by side: payoff dates, total interest, and the plan that fits you.

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.env File Validator & JSON Converter

Paste your <code>.env</code> — get it validated, parsed to JSON, syntax errors with line numbers, and a secret-spotter for the keys you should never commit.

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School Graduation Year & Cohort Calculator

"What year will my kid graduate?" "What year am I supposed to graduate college?" Answer both from a grade, a birth date, or just this year — no more counting on your fingers.

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Overtime Pay Calculator (1.5x, 2x, 3x Holiday Rates)

40 hours at $18 plus 12 hours at time-and-a-half — what's the paycheck? Enter your rate and hours, get the full breakdown in seconds.

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Report Card Comments Assistant

Thirty report cards due Friday? Pick the student profile and subject, get a professional, printable comment — no AI account, no login wall, just a curated phrase bank.

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School Age & Grade 1 Cutoff Date Checker

Which grade should a child born in June 2018 be in? What year do they start kindergarten? Answer both — with your state's cutoff date accounted for.

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Speech Duration & Presentation Word Count

A 5-minute presentation needs how many words? Paste your script (or just the word count) and pick your pace — get the duration, plus a target word count for any time limit.

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Floor & Wall Tile Calculator (Count, Sq Ft & Boxes)

Tiling a bathroom floor or kitchen backsplash? Enter room size, tile size and grout width — get exact tile count, boxes to buy, waste allowance and cost.

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Vacation Travel Budget Planner

Plan your travel expenses and savings target. Add flights, hotels, food and fun — get the total, the per-person share, and exactly how much to save each month.

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XML to JSON & JSON to XML Converter

Legacy SOAP response in one hand, modern JSON API in the other? Convert XML ↔ JSON, format ugly XML, and validate well-formedness — locally.

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SRT Subtitle Time Shifter & Sync Tool

Shift every SRT subtitle timestamp forward or backward and download the corrected file.

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Unicode Homoglyph & Phishing Text Checker

Find mixed scripts, invisible characters, and confusable Unicode code points in text.

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iCalendar .ics Event Generator

Create a standards-friendly .ics calendar event locally from title, time, location, and notes.

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Molarity & Solution Preparation Calculator

Calculate molarity, moles, mass, or solution volume from the values you know.

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SRT Subtitle Frame Rate (FPS) Resync

Retiming SRT subtitle timestamps between common video frame rates.

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Unicode Normalizer (NFC, NFD, NFKC)

Normalize text with NFC, NFD, NFKC, or NFKD and inspect its code points.

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Subtitle Converter (SRT ↔ VTT & Transcripts)

Seamlessly convert between SRT and WebVTT (.vtt) or strip all timestamps and cue numbers to extract clean speech transcripts.

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CSS Grid Visual Layout Builder

Configure columns, rows, and gaps visually to generate CSS Grid layout code.

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All-in-One Percentage Calculator

Three common modes for percentage-of, percentage change, and ratio math.

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