How does the diff algorithm work?

The tool uses the Longest Common Subsequence (LCS) algorithm to find the minimum set of changes between the two texts, similar to the Unix diff command.

What do the colors mean?

Green lines with a + sign are lines that were added in the modified text. Red lines with a − sign were removed from the original. Unchanged lines are shown without color.

Is there a text size limit?

There is no hard limit, but very large texts (thousands of lines) may take a moment to process in the browser.

Yes. All comparison happens in your browser. Your text is never sent to any server.

What does the diff checker compare?

The tool compares text line by line and highlights lines that were added, removed, or changed between the two versions.

Can I compare code files?

Yes. Paste any text including code, and the tool will highlight the differences.

Text Diff Checker — Compare Two Texts Online Free

Compare two texts and highlight differences line by line. Free online text diff checker — no upload required.

Original Text

Modified Text

100% Private

No Upload

Instant

What is Text Diff Checker?

A text diff checker compares two pieces of text and highlights the differences between them. It is useful for comparing document versions, code changes, or any two text strings. Our Text Diff Checker shows additions in green and deletions in red, making it easy to spot changes at a glance.

How to Use Text Diff Checker

1Paste the original text in the left panel.
2Paste the modified text in the right panel.
3Differences are highlighted automatically.
4Green highlights show additions; red highlights show deletions.

Key Features

Line-by-line difference highlighting
Character-level diff for changed lines
Color-coded additions (green) and deletions (red)
Runs entirely in your browser

Benefits

Compare document versions
Review code changes without a version control system
Spot differences in configuration files

Use Cases

Regex101 Alternative Greedy vs Lazy Regex

Why Use Irreva for Text Diff Checker?

Compare document versions

Review code changes without a version control system

Spot differences in configuration files

Runs 100% in your browser — files never leave your device.

No account, no sign-up, no subscription — free forever.

Works on any device: desktop, tablet, or mobile.

Frequently Asked Questions

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