Text Diff Checker
Need to side-by-side line diff of two texts? Text Diff Checker does it in the browser, in a couple of clicks. Parsing, formatting and validation all run in your browser, so API keys, tokens and internal payloads are never transmitted. It is used most by frontend developers checking a token or payload shape. Follows the published specification rather than a loose approximation. Free, unlimited, and free of the upsells most tools of this kind carry.
Key features
- Follows the published specification rather than a loose approximation.
- Reports the line and position of a syntax error instead of failing silently.
- Works on desktop, tablet and phone — no separate app to install.
- Loads in under a second and gives its result in one action.
How to use Text Diff Checker
- Paste your input: Drop the payload, code or value into the box above.
- Run it: Press the action button — errors are reported with their position.
- Take the output: Copy the result, or download it when the output is a file.
Frequently asked questions
- What happens with invalid input? — You get the position of the problem rather than a blank failure, so it is usable as a validator.
- How large an input can it take? — Several megabytes is routine. The limit is your browser's memory, not a server quota.
- Does it follow the official spec? — Yes — the published specification, not a simplified version, so results match your language's own parser.
- Is there a rate limit? — None. There is no server involved, so nothing to limit.