Text Diff Checker
Compare two texts and highlight differences with advanced diff algorithms and side-by-side comparison for document editing and version control. Perfect for writers and document comparison.
Complete Guide: Text Diff Checker
Everything you need to know about using this tool effectively
The Text Diff tool compares two blocks of text and shows the differences between them. It highlights lines that were added, lines that were removed, and lines that stayed the same. A summary reports the count of added, removed, and unchanged lines. The tool uses a line-by-line comparison algorithm and displays results with color coding. All processing happens in the browser.
This tool takes two text inputs (original and modified) and computes a line-level diff. It identifies which lines are unique to each version and which are shared. Added lines appear in green, removed lines in red, and unchanged lines in the default color. The output uses standard diff notation with + for additions and - for deletions.
Reviewing code changes
Compare two versions of a code file to see exactly what lines were added, removed, or modified.
Tracking document revisions
Compare an older version of a document with a newer one to identify all changes.
Checking configuration changes
Diff two configuration files to see which settings were added or changed.
Comparing translations
Compare an original text with its translation to check alignment and spot missing sections.
Paste the original text
Enter the first version of your text in the left input area.
Paste the modified text
Enter the second version in the right input area.
View differences
The tool computes and displays the diff with color-coded highlighting.
Copy or download
Copy the diff output or download it as a text file.
Use for code reviews to see what changed between versions.
Compare configuration files before and after modifications.
The tool works best with plain text. Formatted documents may show many irrelevant changes.
For very long documents, focus on specific sections by pasting only the changed parts.
How does the diff algorithm work?
The tool compares text line by line. Lines present only in the original are marked as removed (red, -). Lines present only in the modified version are marked as added (green, +). Lines in both versions are shown as unchanged.
Can I compare code files?
Yes. Paste code into both input areas and the tool shows line-level differences. It works with any plain text including code in any language.
Is my text uploaded to a server?
No. All comparison happens in your browser using JavaScript. The text never leaves your device.
Can I save the diff output?
Yes. Copy the diff results to your clipboard or download them as a text file.
Does it detect moved lines?
No. The tool performs a line-by-line comparison. Lines that moved appear as a deletion in one place and an addition in another.