JSON Formatter
Beautify, minify and validate JSON — with exact error messages.
How to use the JSON Formatter
- Paste your JSON into the box.
- Tap Format to beautify it, Minify to compress it to one line, or Validate to check it.
- Copy the result, or read the error message to find the broken part.
JSON Formatter FAQs
What does a JSON formatter do?
It takes compact or messy JSON and reprints it with consistent indentation and line breaks, so you can read nested objects and arrays. Minify does the opposite — it strips all unnecessary whitespace for pasting into code or APIs.
Why is my JSON invalid?
The most common causes are trailing commas, single quotes instead of double quotes, unquoted keys, or a missing closing bracket. This validator shows the parser\u2019s exact error message, which usually points at the problem area.
Does this tool send my JSON to a server?
No. Formatting and validation run entirely in your browser with the built-in JSON parser — your data never leaves your device, so API keys and private payloads stay private.
What is the difference between Format and Validate?
Format both validates and reprints the JSON with indentation. Validate only checks it and reports valid or invalid, without changing the text — useful when you want to confirm data before sending it.
Can I format very large JSON files?
Yes, within browser limits — pasting tens of thousands of lines works fine. For multi-megabyte files, a desktop editor is faster, but this tool handles typical API responses instantly.
Free JSON Formatter & Validator — Beautify and Minify JSON
This free JSON formatter covers the classic developer search “json formatter”: paste any JSON and instantly beautify it with clean indentation, minify it to a single line, or validate it — with the exact error message when something is broken, all in your browser.
How to use it, step by step
- Paste your JSON into the editor box.
- Tap Format for indented output, Minify for a compact one-liner, or Validate to check only.
- Copy the result with one tap, or fix the error the message points to.
Popular uses
- API debugging: read a messy API response at a glance.
- Config files: reformat package.json, settings and data files.
- Code reviews: minify a payload before pasting it into a ticket.
- Learning: see how nested objects and arrays are structured.