JSON Formatter
JSON Formatter formats JSON, minifies it, and catches errors, free and in your browser. You paste JSON, and the tool shows it in a readable indented form, or as a compact single line.
Last updated: 30 October 2026 · Free · No signup
JSON is a format for structured data, used by websites, apps, and APIs, but raw JSON is often hard to read because it arrives as one long line or with inconsistent spacing. Formatting it with indentation makes the structure visible: objects, arrays, and nested values become easy to follow, and errors become easier to spot. Minifying does the opposite, shrinking JSON for storage or sending, by removing unnecessary spaces.
If the tool reports an error, it usually means a missing comma, bracket, or quote in the JSON. Check the area around the error first, because JSON is strict: one small mistake stops the whole document from being valid, even if the rest looks correct.
Privacy: this tool runs entirely in your browser — no upload, no signup, and your files never leave your device.
Tidy up messy JSON, minify it or catch its errors — for API and data work.
JSON (input)
Result (output)
How to use JSON Formatter
- Paste your JSON into the box.
- Choose format for a readable version, or minify for a compact version.
- Check the result, and fix any error the tool reports.
- Copy the formatted or minified JSON.
Key facts
| Actions | Format, minify, and error-check JSON |
|---|---|
| Input | JSON text pasted in |
| Upload | None — formatting happens in your browser |
Frequently asked questions
What is JSON?
JSON is a text format for structured data, using objects with named fields and arrays of values. It is widely used by websites and apps to exchange data, because it is readable by both people and programs.
What does it mean to format JSON?
Formatting adds indentation and line breaks so the structure is visible, with nested objects and arrays clearly indented. Minifying removes those spaces to make the smallest possible version for storage or sending.
Why does my JSON show an error?
JSON is strict about commas, brackets, braces and quotes. A missing comma after a field, an unclosed bracket, or a quote in the wrong place will make the whole document invalid, even if most of it looks right. Check around the reported error first.
Is my JSON uploaded when I format it?
No. Formatting happens in your browser only. Nothing is sent to a server and nothing is saved after you close the page.