Format, validate and beautify JSON data online. Paste messy or minified JSON and get clean, indented, colour-highlighted output instantly - no signup required.
This free JSON formatter (also known as a JSON beautifier or JSON pretty-printer) instantly converts compact or unreadable JSON into neatly indented, human-readable text. Paste any raw, minified, or API-response JSON into the left panel and click Format JSON.
The tool doubles as a JSON validator - if your JSON has a syntax error (missing comma, mismatched bracket, unquoted key), the exact error message appears highlighted so you can fix it fast.
A JSON formatter takes raw or minified JSON and adds proper indentation and newlines so it is easy to read and debug. It is also called a JSON beautifier, JSON pretty-printer, or JSON viewer. This tool works the same way as the dev-tools Console but without needing a browser DevTools session.
Yes - 100% free, no account needed. All formatting runs in your browser with the built-in JavaScript JSON.parse / JSON.stringify APIs, so your data never touches our servers.
Paste your JSON and click Format JSON. If the JSON is invalid, a red error box appears with the exact parser message (e.g. Unexpected token } at position 42) so you can locate and fix the issue quickly.
Formatting adds indentation and newlines for human readability. Minifying removes all optional whitespace to reduce payload size - useful before embedding JSON in production HTML or API responses where every byte counts.
This free online JSON formatter, validator, and beautifier instantly transforms raw, minified, or API-response JSON into clean, indented, human-readable output - all inside your browser with no data ever sent to a server. It is ideal for developers who need to inspect API payloads, debug configuration files, or share readable JSON with teammates. The built-in validator pinpoints syntax errors with precise messages so you can fix issues in seconds.
The formatter parses your input using the browser's native JSON.parse() function, which validates the syntax at the same time. The parsed JavaScript object is then re-serialized with JSON.stringify(obj, null, 2) to produce clean 2-space-indented output. Because all processing happens inside your browser's JavaScript engine, the tool works instantly even on large JSON payloads without any network round-trip.
Yes - your JSON content never leaves your computer for processing. The JSON Formatter is 100% client-side: it uses only browser-native JavaScript APIs with no server uploads, no content analytics, and no logging of what you paste. This makes it safe to use with sensitive API responses, configuration secrets, or internal data you cannot share with a third-party server.
There is no hard server-side limit because all processing runs in your browser. In practice, modern browsers handle JSON files up to several megabytes without issue. For very large files (10 MB+), performance depends on your device's available memory and JavaScript engine, but typical API responses and config files format instantly.
The tool works in all modern browsers including Chrome, Firefox, Safari, Edge, and Opera - any environment that supports ES6 JavaScript. No extensions, plugins, or downloads are required. The <details> and <summary> elements used in the UI are supported by every major browser released since 2016.
Browser DevTools can display JSON from network responses, but they require you to be in an active debugging session and don't let you paste arbitrary JSON from other sources. This tool lets you paste any JSON string - from clipboard, a file, or a colleague's message - format it instantly, sort its keys alphabetically, minify it, and copy the result, all without opening DevTools or navigating to a specific URL.