JSON Formatter and Validator
Description
Beautify, minify, and validate JSON data in real-time. Detect errors and ensure your JSON is syntactically correct for seamless integration.
About JSON Formatter and Validator
The JSON Formatter beautifies, minifies, and validates JSON entirely in your browser. Your JSON is always processed locally — no data is uploaded. Optional features such as Open from URL and JSON Schema validation may make outbound requests you control. Paste raw or messy JSON to instantly pretty-print it with consistent indentation, collapse it to a single line, or catch syntax errors before they reach production.
How to use
- Paste or type your JSON into the input editor on the left.
- Choose an indentation style (2 spaces, 4 spaces, or tab) from the configuration panel.
- The formatted, validated result appears instantly on the right — copy it, download it, or view it as a collapsible tree.
- If the JSON is invalid, the editor highlights the error so you can fix it before copying.
Examples
| Example | Input | Output |
|---|---|---|
| Minify | { "a": 1, "b": 2 } | {"a":1,"b":2} |
| Format | {"user":{"id":1}} | { "user": { "id": 1 } } |
Frequently asked questions
Is my JSON uploaded to a server?
Your JSON is formatted and validated entirely in your browser — it is never uploaded. The tool does make two types of optional outbound requests you control: fetching JSON from a URL you enter (Open from URL), and loading a JSON Schema from SchemaStore or a custom URL when you select one in the Schema panel. If you only paste JSON and do not use those features, nothing leaves your device.
What's the difference between beautify and minify?
Beautify (format) adds indentation and line breaks to make JSON human-readable. Minify removes all unnecessary whitespace to produce the smallest valid JSON — useful for reducing payload size in APIs.
Can it handle large JSON files?
Yes. Because processing is client-side, the practical limit is your browser's memory. Multi-megabyte files format without a network round-trip.
Why does it say my JSON is invalid?
Common causes are trailing commas, single quotes instead of double quotes, unquoted keys, or comments — none of which are allowed in strict JSON. The error message points to the position of the problem.