How to use JSON validator & formatter
Validate a JSON document, inspect its structure and download a consistently formatted copy. The check runs when you submit the form. Its inputs are processed in this browser.
How the check works
The document is parsed with the browser’s JSON parser and formatted with two-space indentation. The tool reports root type, node count and maximum nesting depth.
The Overview tab explains the findings. Measured data lets you search individual fields and values, while JSON report shows the complete export. Export JSON to retain a baseline, or print the findings for your own records. Review the report before sharing it: browser characteristics, token claims, and file names can reveal information about your setup.
Read the result in context
Valid JSON is only a syntax result. A schema or application can impose additional requirements. Duplicate object keys follow JavaScript parsing behavior and the last value wins.
Understand the limits
JavaScript numbers have finite precision, so very large integers can change during parsing. Comments, trailing commas and non-JSON numeric values are rejected.
Common questions
Where is the input processed?
In this browser tab. This tool does not submit its input to the site server or a third-party service.
What should I keep with a result?
Record the selected options, browser and time. Review exported values before sharing them. Generated passwords, tokens and HMAC secret keys are excluded from report exports.