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Diff Checker
Compare two texts and inspect added, removed and unchanged lines.
Text comparison
Compare two versions and inspect their line-level differences.
Compare two texts
Enter an original and modified version to inspect added, removed and unchanged lines.
Both texts are compared locally inside your browser and are never uploaded.
About this tool
What is Diff Checker?
A diff checker compares two versions of text and highlights which lines were added, removed or left unchanged. It is useful for reviewing source code, configuration files, documentation and generated output.
Features
Built for fast developer workflows
- Compare two texts line by line.
- Highlight added, removed and unchanged content.
- Switch between unified and side-by-side views.
- Display comparison statistics.
- Copy a plain-text unified diff.
- Process both documents locally in your browser.
Frequently asked questions
Questions about Diff Checker
How does this diff checker compare text?
It compares complete lines and uses a longest common subsequence algorithm to identify unchanged, added and removed lines.
Does it compare individual words?
Not yet. This version performs line-level comparison. Word-level highlighting can be added in a future iteration.
Can I compare source code?
Yes. You can compare source code, JSON, SQL, configuration files, logs or any other plain-text content.
Are the compared documents uploaded?
No. Both texts are compared entirely inside your browser.
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