JSON Formatter & Validator
Paste JSON, then beautify, minify or validate. Your data never leaves this page.
How to format JSON
- Paste your JSON into the box.
- Click Beautify to add indentation, or Minify to remove all spaces.
- If the JSON is invalid, the message shows the position of the first error.
Common JSON mistakes
- Trailing commas after the last item:
[1,2,] - Single quotes instead of double quotes:
{'a':1} - Unquoted keys:
{a:1} - Comments, which standard JSON does not allow
FAQ
Is my JSON sent to a server?
No. Parsing and formatting use your browser’s built-in JSON engine. This makes it safe for configs and API responses, though you should still avoid pasting secrets into any website.
How large a file can it handle?
Several megabytes work fine on modern devices. Very large files depend on your browser memory.
Do you need Base64 instead?
See the Base64 encoder and decoder.