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JSON Formatter and Validator
An API response on one line is unreadable, and a single missing comma stops everything. Paste JSON here to indent it, sort its keys, shrink it back down, or find out exactly where the syntax breaks.
How to use it
- Paste the JSON.
- Choose an indent size and whether keys should be sorted.
- Press format to expand or minify to compress.
Examples
- A one-line API response becomes a readable tree with two-space indentation.
- Minifying a formatted config file often removes a third of its bytes.
- A trailing comma produces a clear parse error naming the position.
Questions people ask
Why does my file fail to parse?
Usually a trailing comma, single quotes instead of double, an unquoted key, or a stray comment — none of which JSON allows, even though JavaScript does. The error message names the position where the parser gave up.
Does sorting keys change the data?
No. JSON objects have no defined order, so sorted keys carry exactly the same information. It is genuinely useful when comparing two config files, because it removes differences that are only about ordering.
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Updated: 2026-08-07