JSON Formatter & Validator
Format and validate JSON online, free. Instantly catch syntax errors and get properly indented output.
Free to useNo software to install — works in any modern browser.
No signup neededOpen the tool and start straight away.
Runs in your browserNothing you enter is sent to a server.
Works on mobileSame tool on your phone, tablet or desktop.
How it works
- Enter — type or paste your values or text.
- Get the result — it is worked out in your browser.
- Adjust — change the inputs to compare, or copy the result.
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About JSON Formatter
This tool checks that your JSON is syntactically valid and reformats it with proper indentation, turning a single dense line of JSON into a readable, structured layout — useful when debugging API responses or configuration files.
If your JSON has an error, the tool reports that it's invalid along with a description of the problem, helping you locate and fix the issue rather than just failing silently.
If your JSON has an error, the tool reports that it's invalid along with a description of the problem, helping you locate and fix the issue rather than just failing silently.
Frequently Asked Questions
What does this tool actually check?
It validates that your JSON is syntactically correct and reformats it with proper indentation.
What happens if my JSON has an error?
The tool tells you it's invalid along with a description of the error.
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