JSON is the standard data format for APIs, config files and web apps — but raw JSON from a server is usually one unreadable line. This formatter pretty-prints it with clean 2-space indentation, minifies it back down, or validates the syntax. Everything runs 100% in your browser: your data is never uploaded or stored anywhere.
Formatting is a two-step round trip: parse, then re-serialize.
JSON.parse() reads your text into a real data structure — this is also where syntax errors are caught, with the exact position reported.JSON.stringify(value, null, 2) writes it back out with 2-space indentation for readable output.JSON.stringify(value) with no indentation, collapsing everything to a single line for compact storage or transmission.Formatting never changes your data's meaning — only its whitespace.
Paste this compact JSON and hit Format:
{"name":"Aarav","city":"Dehradun","skills":["react","node"]}
You get:
{
"name": "Aarav",
"city": "Dehradun",
"skills": [
"react",
"node"
]
}
Formatted output is your JSON with consistent indentation — copy it straight into a config file or API test. Minified output is the same data on one line, useful for embedding in URLs or shrinking payloads. The Validate check tells you whether the JSON is syntactically legal and shows the exact error (e.g. a trailing comma or a missing quote) when it isn't.
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Content last reviewed on 2026-10-06.