Code Diff Checker
Compare two blocks of text or code side by side and highlight every added, removed, and changed line. Free online diff checker, no upload needed.
0
Additions
0
Removals
How to use the Code Diff Checker
- Paste your original text or code into the Original box on the left.
- Paste the updated version into the Changed box on the right.
- The unified diff below updates live — green lines were added, red lines were removed.
- Toggle Ignore leading/trailing whitespace to hide indentation-only changes.
Frequently asked questions
What kind of diff is this?
It’s a line-by-line (unified) diff. Each line is compared as a whole, so any change within a line shows the old line as removed and the new line as added.
What does “Ignore leading/trailing whitespace” do?
When enabled, each line is trimmed before comparing, so lines that differ only in indentation or trailing spaces are treated as identical.
Is there a size limit?
Everything is limited only by your browser’s memory. Very large inputs (many thousands of lines) may take a moment to render.
Are my two texts uploaded anywhere?
No. The comparison runs entirely in your browser — nothing you paste is ever sent to a server or stored.