No trailing commas
Remove the comma after the last item in an object or array.
JSON Formatter & Validator
Paste messy or minified JSON to make it readable, shrink it for production, or find exactly where it is broken. Errors are reported with the line and column so you can fix them fast.
- 100% free
- No sign-up
- Data never leaves your browser
How to use
How to use the JSON Formatter & Validator
- Paste your JSON. It is formatted automatically as you type.
- Choose the indent and whether to sort keys.
- Click Minify for a compact single line, or Validate to check it.
- Copy or download the result.
Private by design. Your code and data are processed in your browser. Nothing is uploaded, logged or stored, so it is safe for API responses, configs and other internal data.
About this tool
Common JSON errors and how to fix them
JSON is strict. Most errors come from a handful of mistakes: a trailing comma after the last item, single quotes instead of double quotes, keys without quotes, comments, or a missing bracket. JavaScript allows some of these, which is why code that works as a JS object can still be invalid JSON.
When something is wrong, the validator shows the line and column where parsing stopped, with a marker under the problem. The real mistake is usually right there or just before it, often a missing comma or quote on the previous line.
Good to know
JSON tips
Double quotes only
Keys and strings must use double quotes.
No comments
Standard JSON does not allow // or /* */ comments.
Minify for production
Minified JSON is smaller to send over the network.
FAQ
JSON Formatter & Validator FAQs
Is my JSON sent to a server?
No. Parsing and formatting happen in your browser, so it is safe for private data.
Can it handle large files?
Yes, files of several megabytes format quickly in modern browsers.
What does Sort keys do?
It orders object keys alphabetically at every level, which makes two JSON files easier to compare.
Why is valid JavaScript showing an error?
JSON is stricter than JavaScript. Quotes, commas and comments are the usual culprits.
Need extra development capacity?
Hire dedicated developers from iCreativez who work as part of your team.