Diff Checker
Compare two versions of a text or code line by line. See added and removed lines side by side, and ignore whitespace or case if you like.
Runs in your browser. Nothing is uploaded.
About the Diff Checker
When two versions of a document, configuration file or piece of code look almost the same, finding what changed by eye is slow and error-prone. A diff lines them up and marks exactly which lines were added, removed or kept.
This is useful for checking edits to a contract or article, comparing configuration between servers, reviewing code outside a version control system, or confirming that a tool's output matches what you expected. Options to ignore whitespace and case hide changes that do not matter, and the result can be copied as a standard unified diff.
How to use the Diff Checker
- 1
Paste the original text on the left and the changed version on the right, or load the sample.
- 2
Press Compare. Removed lines are marked with a minus and added lines with a plus.
- 3
Switch between Side by side and Unified views. Turn on Ignore whitespace or Ignore case to hide changes that do not matter.
- 4
Copy the result as a unified diff to paste into a ticket or code review.
Examples
Orders ship in 2 days.
Returns within 14 days.
---
Orders ship in 1 day.
Returns within 14 days.
Exchanges are free.- Orders ship in 2 days.
+ Orders ship in 1 day.
Returns within 14 days.
+ Exchanges are free.Good to know
- Differences are shown per line. A one-character change marks the whole line as changed.
- Files are compared as plain text: Word, PDF and spreadsheet files need to be copied as text first.
- Line endings (Windows CRLF or Unix LF) are treated as the same.
Frequently asked questions
How does the comparison work?
It uses the Myers diff algorithm, the same approach as git, to find the smallest set of added and removed lines that turns the original into the changed text.
Can I compare code?
Yes. Paste any code or config file. Turn on Ignore whitespace to skip indentation-only changes after reformatting.
What does “unified” view mean?
All lines in one column, with removed lines marked − and added lines marked +, the format used by git diff and patch files.
Is my text uploaded to a server?
No. Everything is processed in your browser. Your text is never sent to our servers or stored anywhere.
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