JSON Formatter & Validator
Beautify, minify and validate JSON. Syntax errors are pinpointed with exact line and column. All local — your data never leaves the browser.
Runs locally in your browser
Input
Output
How to use JSON Formatter
- Paste JSON into the editor.
- Format, minify or validate the document.
- Copy or download the cleaned JSON.
Common use cases
- Inspect an API response during debugging.
- Find a syntax error by line and column.
- Minify a payload before storing it in a fixture.
- Prepare JSON before converting it to a model or YAML.
Good to know
- The input must be valid JSON for formatting to succeed.
- Very large documents depend on available browser memory.
- Comments and trailing commas are not part of standard JSON.
What you can do next
FAQ
Is my JSON sent to a server?
No. Formatting and validation are pure JavaScript in your browser — API responses and configs stay private.
How does error locating work?
When parsing fails, the parser's character offset is converted into a line:column position so you can jump straight to the problem — missing commas and trailing commas are the usual suspects.
Does it support JSON5 or comments?
Not currently — it follows strict JSON (RFC 8259). Strip comments first if your config file has them.