JSON Formatter Online — Beautify and Minify JSON
Format, validate and minify JSON online in your browser. Make API responses, configuration files and logs readable without uploading your data.
About this tool
This JSON formatter parses your input and rewrites valid JSON with consistent indentation. Use the formatted view for debugging and reviews, or minify the same data when you need a compact payload.
How to use
- Paste a JSON object or array into the input field.
- Select Format JSON for readable indentation or Minify for compact output.
- Review the result, then copy it to your editor, request body or configuration file.
Features
- Formats nested objects and arrays with consistent indentation.
- Detects invalid JSON before producing output.
- Minifies valid JSON without changing its values or structure.
Common use cases
- Read an API response or webhook payload more easily.
- Clean up JSON configuration files before code review.
- Reduce whitespace in a payload before storing or transmitting it.
Common issues and tips
- JSON requires double quotes around property names and string values; single quotes are invalid.
- Trailing commas, comments, undefined and JavaScript expressions are not valid JSON.
Privacy
Formatting runs locally in your browser. The JSON you paste is not uploaded to Tools12345.
Frequently asked questions
Does formatting JSON change its data?
No. Formatting changes whitespace and indentation only. Minifying also preserves the parsed keys and values.
Why does valid JavaScript fail as JSON?
JSON is stricter than JavaScript object syntax. It does not support comments, trailing commas, functions, undefined or single-quoted strings.
Can I format sensitive API data?
Processing happens in your browser, but you should still remove secrets before copying the result into tickets, chats or public documents.