Diff Checker
Compare text or code. Export a patch.
Private by design
Your inputs stay on your device and are not sent to our servers. Optional usage analytics does not receive your files or tool inputs.
How to use Diff Checker
- Paste original and changed content or open UTF-8 files. Choose text, JSON, JavaScript, TypeScript, HTML, XML, CSS, CSV, YAML, Markdown, SQL, Python, INI or TOML.
- Compare in a local worker. JSON can be normalized and object keys sorted without rounding number literals. Optional ignore-case and edge-whitespace settings affect visual matching.
- Choose side-by-side or unified view, navigate changes, filter unchanged rows, and copy or download a unified patch. Large results are paged.
What are the limits of Diff Checker?
This is line/word text comparison, not a semantic parser, executable-code analyser, CSV table merge or JSON Patch generator. Only JSON normalization validates syntax; duplicate keys and excessive nesting are rejected. Input is capped at 200 KB and 5,000 lines per side, with algorithm and worker deadlines. CRLF/CR endings are normalized to LF; JSON formatting/key order can be normalized before patch generation. Downloaded patches reflect all prepared-text changes, including ones ignored in the visual view. Inline word highlights are bounded and fall back to whole changed lines on large edits. Text is displayed safely rather than interpreted as HTML.