JSON Formatter & Validator Online
JSON Formatter beautifies messy JSON into clean, indented, readable code and instantly tells you when something is broken. Paste raw JSON from an API response, config file or database, and the tool validates it, highlights the first error with its position, and lets you switch between beautified and minified output. Everything runs locally in your browser — no data is sent anywhere — making it safe for logs and payloads that may contain sensitive values. A daily companion for any developer working with APIs.
How to use JSON Formatter
- 1
Paste your JSON
Paste raw JSON into the input box, or type it directly.
- 2
Format or minify
Click Beautify to indent and structure the JSON, or Minify to strip whitespace.
- 3
Copy the result
If the JSON is valid, copy the formatted output to your clipboard.
Why use this tool
- Beautify and minify JSON with one click
- Instant validation with clear error messages
- Configurable indentation (2, 4 spaces or tabs)
- Private — input never leaves your browser
- Free, fast, no sign-up
Frequently asked questions
- How do I know if my JSON is valid?
- The tool parses your input the moment you format it. If there is a syntax error, a message shows the location so you can fix it.
- Can I minify JSON too?
- Yes. Click Minify to remove all unnecessary whitespace, producing the smallest possible valid JSON.
- Is my JSON sent to a server?
- No. All formatting and validation happen locally in your browser, so your data — including any sensitive values — never leaves your device.
- Can I change the indentation?
- Yes. Choose between 2 spaces, 4 spaces or tab indentation before beautifying.
- What JSON versions are supported?
- The tool supports standard JSON as defined by RFC 8259, including nested objects and arrays.
- Is there a size limit?
- There is no artificial limit — performance depends only on your browser and device memory.
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