JSON Formatter & Validator

JSON formatting and validation explained

JSON (JavaScript Object Notation) has become the universal language of web APIs. Whether you are debugging an API response, reviewing a configuration file, or preparing data for documentation, a good JSON formatter saves enormous amounts of time.

Our formatter validates your JSON first — using the same JSON.parse() engine that every browser and Node.js runtime uses. If your JSON has a syntax error, you get an exact error message pointing to the problem, not a vague failure. Common issues like trailing commas, single-quoted strings, and missing brackets are all caught and reported.

Once validated, the formatter rebuilds your JSON using JSON.stringify() with your chosen indentation. You can choose 2 spaces (popular in JavaScript projects), 4 spaces (common in Python and Java codebases), or tabs (useful when your editor or style guide prefers them).

The minifier does the opposite — it strips all unnecessary whitespace and produces the most compact valid JSON representation. This is useful before sending JSON in HTTP requests, storing it in databases, or embedding it in HTML.

• API debugging: Paste a minified API response and instantly read its structure
• Config files: Format package.json, tsconfig.json, or any other config file
• Data validation: Catch syntax errors before submitting data to a server
• Code reviews: Format JSON snippets to make them reviewable in pull requests

Everything runs in your browser — there is no upload, no server, and no account required. Your JSON data never leaves your device.