JSON Validator & Formatter

Validate, format and repair JSON up to 50 MB. Everything runs in your browser — nothing is uploaded.

Attempt to repair invalid JSON

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Features

Smart Formatting

Automatically formats and indents your JSON with proper structure

Error Recovery

Attempts to repair common JSON errors and format partially valid data

Syntax Highlighting

Beautiful syntax highlighting with line numbers for easy reading

Pro Tips

• Use the checkbox to toggle JSON repair functionality
• The validator can fix missing quotes, trailing commas, and unmatched brackets
• Look up any parse error to see what it means and how to fix it
• Validating replaces your text with the formatted result. To keep the original and choose the indentation, use the beautifier

JSON Data Types

"string"Text values

123Numbers

true/falseBooleans

nullNull value

[...]Arrays

{...}Objects

Your JSON and text are processed entirely in your browser and are never sent anywhere. To understand how the site is used we record each page view — the page, the referrer and an approximate location from your IP address — and keep it for 90 days. Nothing is stored on your device unless you choose it. Accept to also store a device identifier here and record your browser and device characteristics, which is what lets a return visit be told from a new one. Decline and nothing is sent at all. We respect Do Not Track. See our privacy policy.

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