Text & Code Diff Checker
Paste an original and a changed version to see which lines were added or removed. Switch between inline and side-by-side views.
Text & Code Diff CheckerRuns in your browser
Your input stays in your browser and is not sent to a server by this page.
What it is and when to use it
A diff compares two versions of text and marks what was added, removed or left unchanged. It is useful for reviewing edits to code, configuration files, documents and copied content without reading both versions line by line.
How to use
- Paste the original text on the left and the new version on the right.
- Select Compare.
- Choose inline or side-by-side view.
- Use the ignore options to hide whitespace or case-only changes.
Example
Input
Original: let a = 1; Changed: let a = 2;
Result
- let a = 1; + let a = 2;
Tips and common mistakes
- Different line endings (Windows CRLF versus Unix LF) or tabs versus spaces can make every line look changed. Normalize them before comparing.
- For JSON or CSS, format both sides the same way first, so the diff shows real changes instead of layout differences.
- Compare one file or section at a time. Smaller inputs give clearer results and run faster.
- A diff shows what changed, not whether the change is correct. Review the meaning of each change yourself.
Frequently asked questions
Does it compare words or lines?
Lines. A changed line is shown as one removed line and one added line.
Is there a size limit?
Each side is limited to 2,000 lines so the browser stays responsive.
Is my text uploaded?
No. The comparison runs entirely in your browser.