Code Diff Checker
Compare two blocks of text or code securely in your browser. Your code is never uploaded to a server—100% private diff checking with additions in green and deletions in red.
SolveBar's Diff Checker compares two versions of any text or code and highlights exactly what changed — line by line, with additions in green and deletions in red. Useful for code reviews, comparing document revisions, spotting configuration changes, and debugging.
How the diff algorithm works
This tool uses a Longest Common Subsequence (LCS) algorithm — the same approach used by Git's diff command. It finds the minimum set of changes needed to transform one version into the other, giving an accurate and meaningful diff.
Split view vs unified view
Split view shows original and modified side by side, making it easy to read both versions in context. Unified view shows a single column with + and - markers, matching the format used by Git and code review tools like GitHub and GitLab.
Saving diffs for later
The tool saves your last 5 comparisons to localStorage. Label each one before saving so you can quickly identify it later — useful when comparing multiple versions of a config file or reviewing several rounds of document edits.
Frequently Asked Questions
Can I compare code in any programming language?
Yes. The diff works on plain text so any language — Python, JavaScript, SQL, JSON, YAML — is supported.
Is there a size limit for the text I can compare?
No hard limit, but very large files (10,000+ lines) may slow down the browser. For large codebases, use Git diff on the command line.
Are my comparisons saved to a server?
No. Everything runs in your browser. Saved diffs are stored in localStorage on your device only.