Text Diff Online - Free Text Comparison Tool

Compare text and highlight differences. Fast, secure, and completely free. All processing happens in your browser — no data is sent to any server.

What is Text Compare?

Text Compare highlights the differences between two blocks of plain text at the line and word level, using the same class of diff algorithm behind tools like Git's diff or Unix's diff command. It shows exactly which lines were added, removed, or changed, and within a changed line, which specific words differ — which is more precise than a whole-line diff when only a single word or value changed inside an otherwise identical line. This is the general-purpose comparison tool for anything that isn't structured data (for that, the format-specific comparers like JSON Compare or SQL Compare give more precise results).

How to Use Text Compare

1. Paste the original text into the left panel and the revised version into the right panel
2. The comparison runs as you type, with differences highlighted in color
3. Switch to word-level highlighting to see exactly which words changed within a modified line
4. Toggle whitespace sensitivity if you need to ignore trailing spaces or indentation differences
5. Copy the diff output for use in a report, changelog, or code review comment

Key Features

• Line-level and word-level diff highlighting
• Option to ignore whitespace-only differences
• Side-by-side and unified diff view modes
• Handles large blocks of text without needing a separate diffing tool installed
• Runs entirely client-side, safe for internal or unpublished text

Why Use Text Compare?

Not everything you need to compare is structured data — sometimes it's two drafts of a document, two versions of an email template, or plain-text log output before and after a fix. A general-purpose line and word diff is the right tool for exactly that: it doesn't need to understand JSON or SQL syntax, it just shows you precisely what changed between two versions of any text, which is often faster than opening a full version control diff view for a quick one-off comparison.

Common Use Cases

• Comparing two drafts of a document or piece of writing
• Reviewing changes between two versions of a plain-text configuration or log snippet
• Spotting exactly what changed in a copy-pasted error message across two occurrences
• Comparing output from two runs of a script or command
• Checking a translation or localization file against its source for unintended differences

Frequently Asked Questions

What's the difference between this and the format-specific comparers, like JSON or SQL Compare?

This tool treats input as plain text and diffs it line-by-line and word-by-word; the format-specific comparers first parse the input into its actual structure, which produces more precise results for data that follows a known format.

Can I ignore whitespace-only differences, like trailing spaces?

Yes, toggle whitespace sensitivity off to treat lines that differ only in trailing or leading spaces as identical.

Does it handle very long documents?

Yes, though extremely large documents (many thousands of lines) may take a moment to render the full diff since processing happens in your browser.

Can I see the differences side by side instead of inline?

Yes, switch to the side-by-side view to see both versions in parallel columns with corresponding changes aligned.

Is my text uploaded anywhere to generate the diff?

No, the entire comparison runs locally in your browser using JavaScript.

Guides

• Comparing HTML: The Right Way (and Why Text Diffs Lie)

Related Tools

• JSON Compare — Compare and diff two JSON objects
• XML Compare — Compare and diff two XML documents
• CSV Compare — Compare and diff two CSV files