Text Diff Checker

What is a text diff checker?

It compares two documents line by line and aligns them so matching lines stay paired. Lines that appear only in the first text are marked as removed, lines that appear only in the second are marked as added, while identical lines remain unhighlighted.

How should I use it?

• Paste the original text into the left box and the new version into the right box.
• Review the side-by-side view: amber removals on the left, green additions on the right.
• Check the summary tiles for total, added, removed and unchanged line counts.

FAQ

• Is my text uploaded anywhere? No — the comparison runs entirely in your browser and your text never leaves your device.
• Is the comparison case-sensitive? Yes, lines are compared exactly; a line that only differs in capitalization counts as changed.
• How are large texts handled? The comparison is line-based, so pairing stays correct across thousands of lines.

Line or character granularity

Line-by-line diff highlights whole changed rows — ideal for code and configs. Word and character diff zooms into exactly what changed inside a sentence — better for copy editing and proofreading tweaks.

A clean review workflow

Paste the original and the edited version side by side, then scan only the highlighted hunks. That focused review catches accidental deletions that a full re-read of the file often misses — especially after automated edits.