How to Diff Text Online
Compare two texts side-by-side and find every difference instantly. Free online diff checker with line-by-line highlighting, word-level changes, and unified diff output.
Open Diff Checker →Step-by-Step Guide
Paste your two texts
Enter the original text in the left panel and the modified text in the right panel. You can paste code snippets, configuration files, documents, or any plain text you want to compare. The tool handles texts of any length.
View the differences
The diff checker highlights every change between the two texts instantly. Added lines appear in green, removed lines in red, and modified lines show word-level highlighting so you can spot exactly what changed within each line.
Switch between diff views
Toggle between side-by-side view for a clear visual comparison and unified diff view for a compact, git-style output. Side-by-side is best for reviewing changes, while unified diff is ideal for sharing or pasting into code reviews.
Copy or share the diff
Copy the diff output to your clipboard in unified format, ready to paste into pull requests, code reviews, or documentation. The tool runs entirely in your browser so your content never leaves your machine.
Try It Now — Free
No signup, no download. Runs entirely in your browser.
Open Diff Checker