Diff Checker
Compare two text blocks side-by-side. Highlights added, removed, and changed lines instantly.
How to Use
- Paste your original text into the Original field and the updated version into Modified.
- Click Compare to generate a line-by-line diff.
- Green lines are additions, red lines are removals, and neutral lines are unchanged. The summary shows total counts.
Frequently Asked Questions
- How does the diff algorithm work?
- This tool uses the Longest Common Subsequence (LCS) algorithm to find the minimum set of insertions and deletions needed to transform the original text into the modified text.
- Does it support character-level diff?
- Currently, the tool performs line-level diff — each line is compared as a whole unit. Character-level diffing within changed lines is not shown.
- Can I diff code files?
- Yes — paste any plain text including source code, JSON, YAML, or configuration files. The tool handles any text content.