JSON Formatter & Validator
Validate, format, minify, copy and download JSON using a private browser-only utility. No sign-up or server processing required.
Validate, format or minify JSON
Paste JSON into the editor. Parsing and formatting happen entirely in this browser tab.
What makes valid JSON?
JSON is a text format for structured data used in APIs, applications, configuration and publishing workflows. Objects use quoted property names, array entries are separated by commas, and JSON supports strings, numbers, booleans, arrays, objects and null.
Example: {"title":"Example","published":true,"tags":["seo","ads"]}. JavaScript comments, single-quoted property names, trailing commas and bare undefined are not valid JSON.
Safe local workflow
Your input is parsed locally with the built-in JSON parser. Output is placed in a plain text field so it is not executed or rendered as HTML. Use formatting for review or minification to remove unnecessary whitespace. Uploaded files are not required. Note that JSON parsers do not reliably flag duplicated object keys; avoid using duplicate keys in the first place.
Frequently asked questions
Does this send JSON to a server?
No. The editor and processor work locally in your browser. Standard website analytics may operate independently, but this tool does not include your JSON input in analytics events.
Can I validate an API response?
Yes, paste a JSON response and format it to help inspect the structure. Validation checks JSON syntax, not whether the content meets an API’s schema.
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