quialo.

JSON Formatter

Paste JSON above to format it.

Paste raw or minified JSON and this tool formats it into clean, readable, indented output. It validates as you go, so syntax errors show up right away. Everything runs in your browser, which means your data never leaves your device.

How to use

  1. Paste your JSON into the input box, or type it directly.
  2. Choose an indent size: 2 spaces, 4 spaces, or tabs.
  3. Read the formatted output. Any syntax error is flagged with a clear message that points to the problem.
  4. Click Copy to grab the clean JSON, or Reset to start over.

Examples

  • Input: {"name":"Quialo","tags":["fast","simple"],"active":true} Output: the same object expanded across lines with 2 space indentation.
  • Input: a single line array like [1,2,3,{"x":true}] Output: each element on its own indented line, easy to scan.

FAQs

Is my JSON sent to a server?
No. All formatting and validation happen locally in your browser, so your data stays on your device.
What does the validator catch?
It catches syntax problems such as missing commas, unclosed brackets, trailing commas, and invalid quotes, and it points you toward where the problem is.
Can it minify JSON too?
Yes. Alongside formatting, you can compact JSON to a single line to make it smaller for storage or transfer.
Is there a size limit?
There is no fixed limit, but very large files depend on your device memory, since all processing happens in the browser.
Does it support JSON with comments?
Standard JSON does not allow comments, so the validator will flag them. Remove the comments to get valid JSON.

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