Diff Checker
+2-2
Left
Right
Side-by-side diff
1
const value = 42;
2
console.log(value);
1
const value = 43;
2
console.info(value);
The Diff Checker compares two blocks of text line by line and highlights exactly what changed. Paste an original and a modified version of code, configuration or prose to see added and removed lines side by side, with totals for each, so you can review edits without git or an IDE.
No. The tool runs entirely in your browser with JavaScript. Your text never leaves your device, nothing is logged, and it keeps working offline once the page has loaded.
Yes. Format both documents with the JSON Formatter first so they share the same indentation, then paste them here to see only the meaningful changes.
Last updated: October 2026 · Built by Derar Sattouf