JSON formatter and validator
Paste JSON and tap Format to make it readable, Minify to make it compact, or Validate to check it. Errors point to the exact line and column.
Runs in your browser. Nothing you paste is sent to or stored by EpiFive.
How to use it
- Paste your JSON into the box (or tap Sample to try it).
- Choose 2 spaces, 4 spaces or tabs, and tick Sort keys if you want them in A–Z order.
- Tap Format, Minify or Validate.
- Copy or download the result, or fix the error shown at the caret and try again.
JSON rules in one minute
- Keys and strings use double quotes:
{"name": "value"}. - Allowed values: strings, numbers,
true,false,null, objects and arrays. - No trailing commas, no comments, and no
undefinedorNaN.
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Related guides
Questions people ask
Is it safe to paste API responses or config files here?
Yes. The JSON is parsed by your own browser and is never uploaded, logged or stored. Still, rotate any real API keys or passwords you have pasted anywhere they did not belong.
What are the most common JSON errors?
A trailing comma after the last item, single quotes instead of double quotes, keys without quotes, comments (JSON does not allow them), and a missing closing bracket. The error message shows the line and column so you can find the problem quickly.
What does minify do?
Minify removes all the spaces and line breaks that are not needed, which makes the JSON smaller to send or store. The data itself does not change.
Why would I sort keys?
Sorting keys alphabetically makes two JSON files easy to compare in a diff tool, because the same keys appear in the same order. Arrays keep their order, since order matters in an array.
Are big numbers kept exactly?
JavaScript numbers are exact up to 9,007,199,254,740,991. Larger integers, such as some 64-bit IDs, may be rounded when formatted, so keep such IDs as strings in your JSON.