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.

Ignore whitespace Ignore case

Original

Changed

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<div style="font-size:12px;color:#78716c;margin-top:6px;font-family:sans-serif;">Powered by <a href="https://lucentool.com/diff-checker" target="_blank" style="color:#c85a32;text-decoration:none;">Lucentool - Text & Code Diff Checker Side-by-Side</a></div>

HTML Embed Code (iframe):

<iframe src="https://lucentool.com/diff-checker" width="100%" height="650" style="border:1px solid #e5e0d8;border-radius:12px;max-width:850px;width:100%;" frameborder="0"></iframe>
<div style="font-size:12px;color:#78716c;margin-top:6px;font-family:sans-serif;">Powered by <a href="https://lucentool.com/diff-checker" target="_blank" style="color:#c85a32;text-decoration:none;">Lucentool - Text & Code Diff Checker Side-by-Side</a></div>

How diff works

This tool uses a simple LCS (longest common subsequence) algorithm to find the minimal set of changes between two texts. Words in red were removed; words in green were added. Unchanged text stays neutral.

When to use

Before/after refactoring: confirm only the intended lines changed.
Config file versions: spot what a teammate changed.
Writing edits: see revisions clearly.

All processing happens client-side — nothing is uploaded.

Text & Code Diff Checker Side-by-Side

How diff works

When to use

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