Populardev

JSON Validator

Validate JSON syntax and get parser error messages for invalid input. Free, fast, and 100% client-side.

About this tool

Use this JSON validator to check whether a JSON string can be parsed successfully. It helps catch common syntax mistakes before you paste JSON into code, configs, or API tools.

How to use

  1. Paste your JSON into the input area.
  2. Run validation to check whether the JSON can be parsed.
  3. If an error appears, review the message and fix the syntax in your input.

Example

Finding a missing comma

If an object has two properties without a comma between them, validation fails and the error message helps you locate the part of the JSON that needs attention.

How it works

What validation means here

The validator checks whether the input can be parsed as JSON and reports basic syntax errors. It does not validate the data against a custom schema or business rules.

Frequently Asked Questions

Does this validate against a JSON schema?

No. This tool checks JSON syntax only and does not compare the data to a schema.

What errors can it catch?

It can catch parse errors such as missing commas, unquoted keys, invalid strings, and extra trailing characters.

Is my JSON uploaded?

No. Validation runs in your browser.

Related Tools

View all