Reviewing code diffs side by side: spotting changes and merging snippets offline

You changed a function, a teammate changed the same file, and now you need to know exactly what is different. The Code Diff Merger compares two snippets side by side in your browser, with counts of added, removed and unchanged lines.

How to compare two versions

• Paste the original code on the left and the new version on the right.
• Green lines were added, red lines were removed, and plain lines are the same in both.
• Check the totals first: a small edit that shows hundreds of changed lines usually means indentation or line endings changed.

Why long lines can look out of place

Each side wraps long lines to fit its column. When one version has a long line and the other a short one, rows can look uneven even though the comparison is correct. Widen the window, or compare formatted code, so matching lines stay easy to follow.

Pick the right level of detail

• Line comparison suits code and config files, where each line means something on its own.
• Word or character comparison suits prose, renamed variables, typos and changed numbers. Use the Diff Checker when one changed word should not mark the whole line.
• Structured comparison suits data. The JSON Compare tool ignores key order and points to the exact path that changed.

Tips for cleaner diffs

• Format both versions the same way before comparing, so spacing changes do not hide real ones.
• Compare one function or section at a time instead of a whole large file.
• Exploring an unfamiliar project first? Open it in the Source Code Explorer, then copy the files you want to compare.

Your code stays private

The comparison runs entirely on your device. Nothing is uploaded, so internal logic, keys and settings in your snippets never leave your browser.