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Developer tools / Free online tool

JSON Validator

Check JSON syntax and find malformed documents before they reach your application.

Runs in your browser
0 characters
OUTPUT
Your result will appear here

A little input. A useful output.

Ctrl + Enter to run

Your input stays on your device. No uploads. No account. Just your result.

How to use JSON Validator

  1. 01

    Paste the document.

  2. 02

    Select Validate JSON.

  3. 03

    Correct any syntax problems and validate again.

A quick example

Try a simple example

INPUT
{"ready":true}
OUTPUT
Valid JSON. Your document follows the JSON syntax rules.

About JSON Validator

Validation checks JSON grammar. It does not enforce business rules or a particular JSON Schema.

When it comes in handy

  • Check an API payload.
  • Validate a configuration file.

Why use it here?

  • Runs locally in your browser.
  • No account needed; copy or download your result.

A few things to keep in mind

  • No JSON Schema validation.
  • Duplicate object keys follow JavaScript parsing behavior.

Good questions. Simple answers.

Does it check required fields?

No. Syntax validation does not check domain rules, field types, or required properties.

Is my input uploaded?

No. This tool processes your input in your browser. Your input and output are not included in analytics.

A good next step

Useful tools that go well together.

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