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JSON Formatter & Validator

Paste JSON to instantly validate, beautify, or minify it. Syntax errors are pinpointed as you type. Everything runs locally in your browser. To transform and route JSON between APIs automatically, use an Autonoly agent.

Paste JSON

Formatted

What this JSON formatter does

This free tool does three things: it validates JSON (telling you exactly where and why it's broken), beautifies it with clean 2-space indentation so it's readable, and minifies it into a single compact line for production. It's the fastest way to make sense of an ugly API response or catch the trailing comma that's breaking your config.

How to format JSON

  1. Paste your JSON into the left box.
  2. It's validated and beautified on the right as you type. If it's invalid, you'll see the exact error message.
  3. Use Minify to compress it, or Copy to grab the result.

Common uses

  • Debugging API responses — paste a raw response to read its structure at a glance.

  • Fixing config files — find the syntax error breaking your package.json or CI config.

  • Cleaning up exports — turn machine-minified JSON into something a human can review.

Privacy

Everything runs in your browser. Your JSON is never uploaded — safe for API keys, tokens, and internal data.

Automate JSON workflows

Formatting is a one-off. Moving JSON *between systems* is the real work: pulling it from one API, reshaping the fields, and posting it to another. An Autonoly agent does that end-to-end on a schedule — fetch, transform, deliver — without writing integration code.

Automate JSON between your apps

Let an AI agent do this automatically, on a schedule, across thousands of records.

Try Autonoly free

FAQ

Common Questions

Everything you need to know about JSON Formatter & Validator.