📌 Overview

Validate JSON syntax and pretty-print valid input. Instantly see the exact error location when your JSON is broken, then copy clean formatted output.

✅ JSON Validator

Validate JSON syntax and pretty-print valid input. Instantly see the exact error location when your JSON is broken, then copy clean formatted output.

JSON

Paste JSON and click Validate.

🔒 All processing happens in your browser. No data is uploaded to any server.

📋 How to Use

Paste your JSON into the box.
Click "Validate".
Read the formatted JSON or the error message.
Copy the cleaned output.

❓ FAQ

How does it show errors?

It uses the browser JSON parser and reports the error text, which usually includes the approximate position of the problem.

Does it fix the JSON for me?

No. It tells you what is wrong; you fix it. Valid input is pretty-printed with indentation for clarity.

Is large JSON supported?

Yes for typical payloads. Extremely large files may be slow since everything runs in the browser.

❓ More Questions

How are errors shown?

It uses the browser JSON parser; the error message usually includes the approximate position of the problem.

Will it fix my JSON for me?

No - it only points out the problem; you fix it yourself. Valid input is pretty-printed with indentation.

💡 Use Cases

🔌

API Debug

Check responses before parsing.

📋

Config

Validate settings files.

🧪

Testing

Verify fixtures are valid.

🔗 Related Tools

📖 Deep Dive: JSON Validator

Why validate JSON

JSON is the de-facto standard for APIs and config; one extra comma or a missing quote breaks the whole parse. Validating early saves a lot of debugging time.

How it works

The tool hands the input to the browser's JSON parser: on success it returns the formatted object; on failure it catches the exception and shows the error description (usually with a position) to help you locate the problem fast.

A quick example

A JSON response throws a parse error; paste it in and click validate, and you immediately see unexpected character near position 142 - fix it and you are done.