JSON Formatter / Validator
Format, validate, and beautify JSON. Detect syntax errors.
Developer Tools: use this free online json formatter / validator in your browser. No signup, no data sent to our servers—instant results.
What this tool does & how to use it
What is this tool?
The JSON formatter and validator helps developers and anyone working with JSON data. Paste minified or messy JSON and the tool formats it with indentation and line breaks so it’s easier to read. It also checks for syntax errors and reports where the problem is.
JSON (JavaScript Object Notation) is used in APIs, config files, and web apps. Valid, well-formatted JSON is easier to debug and maintain.
How to use it
Paste your JSON string into the input area. The tool will format it and highlight any syntax errors (e.g. missing commas, extra brackets). Fix the reported issues and format again until the output is valid. You can copy the formatted result for use in your project.
Benefits
Runs in the browser; your JSON is not uploaded to a server. Instant formatting and validation. Clear error messages help you fix invalid JSON quickly.
Use cases
Formatting API responses for readability. Validating JSON before sending to a server. Debugging config files or data exports. Learning JSON structure by seeing properly indented output.