Text Diff|Options
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Original Text
Modified Text
Diff Output
Differences will appear here as you type.
Additions: 0
Deletions: 0
Unchanged: 0

Text Diff Checker Online — Compare Two Texts & Highlight Every Difference

Need to spot exactly what changed between two versions of a document, email, or code snippet? This free diff checker compares two texts side by side and highlights every addition, deletion, and modification in color.

How to Use This Tool

  1. Paste the original text — Enter or paste the first version of your text in the left input panel.
  2. Paste the changed text — Enter or paste the second version in the right input panel.
  3. Compare — Click the Diff button to compare. Differences are highlighted: green for additions, red for deletions.
  4. Review changes — Scroll through the diff output to see exactly what was added, removed, or modified between the two versions.
  5. Chain with other tools — With Auto-fill enabled, your output automatically carries over when you open another tool from the sidebar. Use the back and forward arrows to undo navigation and restore your previous tool state including all options.

Features

Side-by-Side Comparison

Two input panels let you paste original and changed text next to each other for easy comparison.

Color-Coded Differences

Additions are highlighted in green, deletions in red, making it immediately clear what changed.

Word-Level Precision

Differences are detected at the word level, so you can see exactly which words were added, removed, or changed.

Works with Any Text

Compare documents, emails, code, configuration files, legal contracts, or any other text content.

Instant Processing

Diffs are computed in your browser with no server round-trip.

Complete Privacy

Both texts stay in your browser. Nothing is ever transmitted or stored.

Auto-fill Pipeline

Enable Auto-fill to carry your output to the next tool. Navigate back and forward with full state restoration — input, output, and all settings are preserved.

Real-World Use Cases

1

Compare document versions before publishing

Paste the original and revised versions of a document to see exactly what changed — additions, deletions, and unchanged sections — before approving the final version.

2

Review config file changes to verify edits

Compare two versions of a configuration file to ensure only the intended changes were made and nothing was accidentally modified.

Frequently Asked Questions

What is a text diff?
A diff (short for difference) is a comparison between two texts that identifies what was added, removed, or changed. It is a fundamental concept in version control, editing, and proofreading.
What do the colors mean?
Green highlighting indicates text that was added in the second version. Red highlighting indicates text that was deleted from the first version. Unhighlighted text is identical in both versions.
Can I compare code with this tool?
Yes. The diff checker works with any plain text including source code, configuration files, JSON, XML, and more. It compares content character by character regardless of the language or format.
Does it detect moved text?
The tool detects additions and deletions. If text was moved from one location to another, it will appear as a deletion at the original location and an addition at the new location.
Is there a size limit?
There is no hard limit. The diff runs in your browser, so performance depends on your device. It handles documents of tens of thousands of words comfortably.
Is my text private?
Yes. Both texts are processed entirely in your browser. Nothing is ever sent to a server or stored.

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All text processing happens directly in your browser. Your text is never sent to any server, stored, or shared with third parties. This tool is completely private and secure.