JSON Formatter / Validator
Format, minify, and validate JSON. Pretty-print with indent, compact for APIs. Free online JSON formatter and validator.
JSON formatter and validator
Result
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What is this?
A JSON formatter makes JSON readable (pretty-print) or compact (minify). A validator checks if JSON is well-formed and reports errors. JSON is the standard data format for APIs and configs. Pretty-printing adds indentation and line breaks so you can read nested structures. Minifying removes whitespace to reduce size for APIs and storage. The validator catches syntax errors like trailing commas, unquoted keys, or mismatched brackets. All processing runs in your browser—your data never leaves your device.
When to use
Use to debug API responses, format config files, or validate JSON before sending. Example: Minified {"a":1,"b":2} → formatted with indentation. Invalid JSON shows parse error. Developers debug API responses daily. Config files are easier to edit when formatted. Validate JSON before sending to an API to catch errors early. Reduce payload size by minifying. Essential for anyone working with JSON.
How to use
Paste your JSON and choose Format (pretty-print), Minify (compact), or Validate. Format uses 2 or 4 spaces. Invalid JSON shows the parse error. All processing runs in your browser.
Frequently asked questions
- Formatting (pretty-printing) adds indentation and line breaks to make JSON readable. Minifying removes extra whitespace for smaller file sizes.
- Check for trailing commas, unquoted keys, single quotes instead of double quotes, or invalid escape sequences. JSON requires double quotes for strings.
- No. All processing runs in your browser. Your data never leaves your device.