JSON Formatter
Format, validate and minify JSON with precise error locations — right in your browser.
Your JSON never leaves your browser. You can confirm no network requests are made in your browser's developer tools.
What is this tool?
A free JSON formatter that pretty-prints, validates and minifies JSON. Errors are reported with the exact line and column plus a hint for common mistakes, so you can fix broken JSON quickly.
How to use
- Paste your JSON into the input area.
- Choose an indent style (2 spaces, 4 spaces or tabs) and optionally sort keys.
- Switch between Pretty and Minify, then copy or download the result.
Use cases
- Inspecting API responses during development or debugging.
- Minifying configuration files before committing them.
- Finding why a JSON payload fails to parse, with hints for typical copy-paste issues.
Notes
- All processing happens locally. Your input is never uploaded.
- Key sorting orders keys alphabetically (A–Z).
FAQ
Is my JSON uploaded to a server?
No. Formatting, validation and minification all run locally in your browser. Nothing you paste is sent anywhere.
What kinds of errors can it detect?
It pinpoints the exact line and column of syntax errors and gives hints for common issues such as trailing commas, single quotes, smart quotes, comments and truncated input.
Is there a size limit?
There is no hard limit. For input over 1MB, syntax highlighting is disabled automatically to keep the page responsive, but formatting still works.
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