Diff Checker Online

Use this online diff checker to compare text online, review code snippets, and highlight added, removed, or changed lines. Everything runs locally in your browser.

Paste two versions to compare them locally.

0 lines, 0 words

0 lines, 0 words

0
Added lines
0
Removed lines
0
Unchanged lines
0%
Changed share

Diff result

Green lines were added. Red lines were removed.
The comparison result appears here.

Private browser comparison

The diff is computed with local JavaScript. Your snippets, drafts and configs are not sent to an upload endpoint.

Useful for code and copy

Compare release notes, prompts, email drafts, config changes and code snippets without opening a desktop diff app.

Line and word highlights

The checker aligns matching lines and marks word changes inside nearby removed and added lines.

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Frequently Asked Questions

Is my text uploaded to Convertr?

No. The diff checker runs entirely in your browser with JavaScript, so pasted text is not uploaded to Convertr servers.

What changes does the text diff checker show?

It compares lines first, then highlights word-level changes inside changed line pairs when possible.

Can I ignore whitespace differences?

Yes. Enable the ignore whitespace option to collapse spacing before comparing lines.

Text Diff Checker

Compare two text or code versions and highlight added, removed, and changed lines.

Input
An original text and revised text plus comparison options.
Output
A line-oriented difference view and summary.
Real limitations
The comparison is textual rather than semantic, so moved blocks, formatting-only changes, and very large inputs can be noisy or device-limited.
Privacy and data handling
an original text and revised text plus comparison options is processed in this browser tab. Convertr does not receive or store it; closing or reloading the page clears the working state unless the tool explicitly offers a local download.

How to use this tool

  1. Provide an original text and revised text plus comparison options in the tool controls.
  2. Choose the settings that affect a line-oriented difference view and summary, then run the tool.
  3. Review a line-oriented difference view and summary before copying or downloading it.

Common failure modes

Empty sides are valid but produce all-add/all-remove output; extremely large text can exceed browser memory or take longer to compare.

Useful example

Compare two configuration snippets to identify one changed value and one newly added line.