Text Diff Checker

Compare two texts and highlight differences

100% In-BrowserNo Server UploadFree, No Signup
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How to Use

  1. Enter two texts

    Enter Text A and Text B in the input area, separated by a line containing only "---".

  2. Set options

    Use the toolbar to toggle whitespace ignore and set context lines.

  3. Review diff

    The output shows a unified diff. Added lines start with "+", removed lines with "-".

Text Diff Checker Examples

Basic text diff

Input
apple
orange
grape
---
apple
banana
grape
melon
Output
 apple
-orange
+banana
 grape
+melon

"-" indicates removed lines, "+" indicates added lines

Code change diff

Input
const x = 1;
const y = 2;
return x + y;
---
const x = 1;
const y = 3;
const z = 4;
return x + y + z;
Output
 const x = 1;
-const y = 2;
-return x + y;
+const y = 3;
+const z = 4;
+return x + y + z;

Features

  • Line-based diff comparison (LCS algorithm)
  • Unified diff format output (+/- prefixes)
  • Rich HTML display (green for added, red for removed)
  • Ignore whitespace option
  • Configurable context lines
  • Local processing (your input is not sent to servers)
  • Dark mode support

FAQ

How do I separate the two texts?

Place a line containing only "---" (three hyphens) between Text A (above) and Text B (below) in the input area.

Can it handle large texts?

Yes, within browser memory limits. Very large texts may take longer to process.

Is my data sent to a server?

No. Everything runs locally in your browser and nothing is uploaded.