JSON Formatter & Validator
Paste your JSON to format it with proper indentation, validate its syntax, or minify it for transport. Everything runs in your browser — nothing is sent to any server.
Format, validate, or minify JSON directly in your browser. Paste JSON into the editor to check whether it parses correctly, then produce either readable indented output or compact one-line output without sending the content to a server.
How to format and validate JSON
- Paste or type JSON into the input area.
- Wait for the live validation status or choose Format to parse and pretty-print the JSON.
- Choose Minify when you want the same parsed data serialized without extra indentation or spacing.
- Fix any parse error shown in the status area, then copy the valid output.
Formatting, validation, and minification
The formatter uses the browser's JSON parser. Valid JSON is parsed and serialized again, which normalizes insignificant whitespace and confirms that the input follows JSON syntax. Pretty output uses two-space indentation, while minified output removes formatting whitespace between tokens.
JSON syntax is stricter than JavaScript object syntax. Property names and string values require double quotes, comments are not allowed, trailing commas are invalid, and special JavaScript values such as undefined or NaN are not valid JSON. Parsing errors are reported so you can correct the source instead of receiving guessed output.
Privacy and limitations
JSON parsing and formatting run locally in your browser and do not require the pasted data to be uploaded to Votilo. This tool validates syntax, not the meaning or schema of the data. A valid JSON document can still contain incorrect, unsafe, or unexpected values.
Frequently asked questions
Does formatting change my JSON data?
It reparses and serializes the JSON, changing presentation whitespace but preserving the parsed JSON value.
What indentation does Format use?
Pretty output is serialized with two spaces per indentation level.
Can JSON contain comments?
No. Standard JSON does not allow comments.
Why is a trailing comma rejected?
Trailing commas are not valid in standard JSON, even though some programming languages allow them in object or array literals.
Is pasted JSON sent to Votilo?
No. Parsing and serialization happen in the browser.