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How to Use This Tool
Paste original text
Enter the original version in the left panel.
Paste modified text
Enter the changed version in the right panel.
Review differences
Additions, deletions, and changes are highlighted line by line.
Features
Side-by-Side Diff
View original and modified text in a clear two-panel layout.
Syntax Highlighting
Additions in green, deletions in red, changes highlighted inline.
Instant Comparison
Differences are computed in real time as you edit either panel.
Sample Data
Load example text to see the diff tool in action.
Frequently Asked Questions
What is a diff?
A diff (short for difference) compares two pieces of text and highlights what was added, removed, or changed. Diffs are fundamental to version control systems like Git and are used for code review, document comparison, and change tracking.
What diff algorithm is used?
This tool uses the Myers diff algorithm, the same algorithm used by Git. It finds the minimal set of changes needed to transform one text into another.
Can I compare code files?
Yes. The diff tool works with any text, including source code. For best results, paste the full content of each file version.
What do the colors mean?
Green highlights indicate additions (text present in the modified version but not the original). Red highlights indicate deletions (text present in the original but removed). Yellow highlights indicate lines that were modified.