Free Online JSON Validator & Linter

Have you ever encountered broken JSON and can't figure out what's wrong? This JSON Validator—also known as a JSON Linter—makes the process painless. Paste your JSON directly into the editor or upload a file, and within seconds, you'll see your JSON, what's valid, and what needs fixing. This tool is helpful when you are debugging an API response or tidying up a config file, it helps you keep your JSON clean and error-free without installing anything.

How to Validate JSON Online

Step-by-step guide:

  1. Paste your JSON into the input box above or upload a file from your computer.
  2. If needed, tweak the validation settings to allow comments or trailing commas.
  3. Hit the Validate JSON button.
  4. See if your JSON is valid or get clear feedback on what needs fixing.
  5. Use the Compress button to minify your JSON for faster performance.
  6. Done! Copy your validated JSON back into your project.

Why Choose ConvertLoom's JSON Validator?

  1. No installs. No signup. Just paste your JSON and go.
  2. Acts as both a JSON Validator and JSON Linter.
  3. Catch syntax errors in real time.
  4. Auto-format messy JSON into a clean, readable structure.
  5. Supports advanced options like single quotes, comments, and trailing commas.
  6. Works with large JSON files without slowing you down.
  7. Free to use as often as you need.
Think of it as a JSON lint tool built right into your browser—it checks your syntax, formats your data, and ensures your JSON is production-ready.

Frequently Asked Questions

Q: What does a JSON Validator do?

A: This JSON Validator tool will check your JSON for mistakes like missing brackets, extra commas, or incorrect characters.

Q: Is this JSON Validator also a linter?

A: Yes! It works just like a JSON linter. It scans your JSON, highlights mistakes, and formats the output so you can use it right away without issues.

Q: Can this tool handle large JSON files?

A: Yes! Just upload your file or paste your json in input, and the validator will process it regardless of its size. This tool supports large JSON files.

Q: Is it safe to use this online?

A: Absolutely. Everything runs directly in your browser. Your JSON isn't stored or sent anywhere—it stays on your device.

Q: Can I allow comments or single quotes in my JSON?

A: Standard JSON doesn't support comments or single quotes, but our validator lets you enable those options if you work with slightly looser formats.

Q: Does the JSON Validator format the code, too?

A: Yes. When you validate your JSON, it automatically formats the output, making it easier to read and debug.