Diff Checker

We use the diff library's line-diffing algorithm, which implements a longest-common-subsequence (LCS) approach. This produces minimal, human-readable diffs that match what you'd see in git or VS Code.

Yes. The diff checker works with any plain text - code, config files, logs, prose, JSON, CSV, and more. Red lines are removals, green lines are additions, gray lines are unchanged.

The diff algorithm compares lines, not characters. If you changed whitespace within a line, the entire line may appear as removed-and-added. For word-level or character-level diffs, use a dedicated diff tool. This checker is optimized for code and text where changes typically span entire lines.

Yes. The diff checker handles mixed line endings (LF, CRLF). It normalizes line endings during comparison so that a file converted from Windows to Unix line endings won't show every line as changed.

Absolutely. The diff checker works with any plain text — prose, config files, logs, JSON, CSV, YAML, markdown, and more. Red lines are removals, green lines are additions, gray lines are unchanged. It's content-agnostic and works line-by-line.

The tool handles typical diff use cases instantly. For very large files (10,000+ lines), performance may slow slightly but will still work. Your data stays local - nothing is uploaded.