JSON Formatter & Validator

JSON is everywhere. APIs, config files, local storage, database exports, webhook payloads — it's the format that practically runs the internet. But raw JSON, especially from production APIs, is often a wall of text with no line breaks or indentation. That's where a formatter comes in.

Paste your minified or messy JSON into the input box, hit Format, and you'll instantly get a properly indented, human-readable version. You can choose between 2-space or 4-space indentation depending on your team's style guide or personal preference.

Validating JSON is something developers do constantly — and often discover the problem is a trailing comma, a missing quote, or a mismatched bracket. Our tool parses the JSON with native JavaScript and shows you the exact error message with a position indicator, so you can jump straight to the problem instead of squinting at lines of text.

Minifying JSON removes all whitespace and newlines, reducing file size. This is useful when you're embedding JSON in a request payload, storing it as a string in a database, or optimizing assets for production. A nicely formatted JSON object can easily be 3x the size of its minified version.

When would you actually use this? Debugging an API response that came back broken. Reading a config file someone sent you as a single line. Preparing a JSON body to paste into Postman. Checking whether the data your app is producing is valid before you write unit tests for it.

The tool processes everything in your browser. No data is sent to any server. You can safely paste API keys, private configs, or sensitive data without worrying about it being logged or stored.

We've kept the interface deliberately simple — input on the left, output on the right, error message in plain English at the top. No ads, no distractions, no sign-up required.