About this tool
The JSON Formatter is a free online tool that beautifies, validates, and minifies JSON data instantly in your browser. If you have ever pasted a wall of compressed JSON from an API response and struggled to read it, this tool will reformat it with clean indentation in one click. If you need to send compact JSON in a URL, request body, or storage field, the minify mode strips all whitespace to save bytes.
How it works
1
Paste your JSON
Copy any JSON from an API response, config file, or log and paste it into the input. Whitespace and formatting from the source do not matter.
2
Choose Format or Minify
Click Format to beautify with 2-space indentation. Click Minify to strip all whitespace. The tool parses the JSON first - if it is invalid, you see the exact error message.
3
Copy the result
The output is shown as formatted JSON. Copy it with one click.
Frequently Asked Questions
Is my JSON sent to a server? v
No. Parsing and formatting happen entirely in your browser using JSON.parse() and JSON.stringify().
What is the maximum JSON size? v
The practical limit is the memory available to your browser tab - usually several hundred megabytes.
Why does my JSON show an error but it looks fine? v
Common issues: single quotes instead of double quotes, trailing commas, comments, unquoted object keys, NaN or Infinity values.
Can I convert JSON to YAML or CSV? v
Not in this version. The formatter is focused on JSON only.
Is this free? Do I need to sign up? v
Completely free. No signup, no email. Runs entirely in your browser.
Does it support JSON5, JSONC, or JSON Lines? v
No. This tool validates strict RFC 8259 JSON.