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Free online tool · JSON validator

JSON Validator Online – Free JSON Syntax Checker

Check whether a JSON document is valid before sending it to an API, saving a configuration file or passing it to another tool. Toolora parses your JSON directly in the browser and reports syntax errors.

Having trouble with the embedded tool? Open JSON Validator Online – Free JSON Syntax Checker in Toolora.

What is JSON Validator Online JSON Syntax Checker?

Check whether a JSON document is valid before sending it to an API, saving a configuration file or passing it to another tool. Toolora parses your JSON directly in the browser and reports syntax errors.

How to use this tool

  1. Paste your JSON into the input box.
  2. Click Run to validate the document.
  3. If it fails, use the error message to locate the syntax problem.

Example

Example input

{"name":"Toolora", "items":[1,2,]}

Example result

Invalid JSON: trailing comma before ]

Frequently asked questions

What does a JSON validator check?

It checks whether the text can be parsed as standard JSON syntax.

Why is my JSON invalid?

Common causes include missing quotes, unmatched braces or brackets, trailing commas and malformed values.

Is this JSON validator free?

Yes. You can validate JSON online without installing software.