JSON Validator
Validate JSON syntax and check for errors. Get detailed error messages and line numbers.
JSON Input
Introduction
The JSON Validator tool checks whether your JSON data is syntactically correct and shows clear error messages when something is wrong. It is ideal for debugging API payloads, config files, and test data before they reach production.
When to use this tool
Use this tool whenever you need to confirm that JSON is valid: before sending a request to an API, committing configuration changes, sharing examples in documentation, or importing data into another system.
How to use
Paste or upload JSON data
Paste JSON directly into the input area or copy it from logs, API clients, or configuration files that you want to verify.
Run validation
Click the validate button to parse the JSON and quickly detect any syntax errors such as missing commas, braces, or quotes.
Review error details
If the JSON is invalid, check the reported line and column to pinpoint exactly where the problem occurs.
Fix and revalidate
Correct the JSON based on the error message, then run validation again until the tool confirms that the data is valid.
Examples
Catching typos in API requests
Before sending a complex JSON body in a POST request, validate it here to catch subtle syntax mistakes that would otherwise cause 4xx errors.
Verifying configuration files
When editing JSON-based config files for services or applications, paste the final version into this tool to make sure there are no trailing commas or invalid values.
FAQ
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