JSON Formatter
Prettify and validate your JSON data for better readability.
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Quick Tip
Paste your JSON into the input box.
About This Tool
Why use JSON Formatter?
Paste minified or messy JSON and get it back indented with two spaces, or an error message telling you exactly where the syntax breaks. Validation and formatting happen in the same step: if the text parses, you get formatted output; if it does not, you get the parser's message.
Most JSON errors come from a short list: a trailing comma after the last item, single quotes instead of double, unquoted keys, or a stray control character pasted from a log. The parser reports the position, which usually points at the character just after the real mistake.
Key Benefits
Formats and validates at once
Valid JSON is indented; invalid JSON produces the parser error instead of silent, broken output.
Nothing is uploaded
Parsing happens in your browser, so API responses containing tokens or customer data never leave the machine.
Handles large payloads
Long lines wrap and the output scrolls inside its panel rather than stretching the page.
How to use JSON Formatter
- 1
Paste your JSON into the input box.
- 2
The formatted result appears immediately; there is no button to press.
- 3
If the input is invalid, read the error message and check the position it names.
- 4
Copy the formatted JSON, or download it as a .json file.
Best use cases
Make an API response readable while debugging.
Check that a config file is valid before deploying it.
Tidy JSON before pasting it into documentation or a ticket.
Find the item causing a parse error in a long payload.
JSON Formatter FAQs
Why does my JSON say it is invalid?
The usual causes are a trailing comma after the last element, single quotes instead of double quotes, unquoted property names, or comments — JSON allows none of these. The error message gives the character position where parsing failed.
Is my data sent to a server?
No. Formatting runs entirely in your browser, so nothing is uploaded, logged or stored.
What indentation does it use?
Two spaces, the most common convention in JavaScript and configuration files.
Can it handle JSON Lines or multiple objects?
Not directly. JSON Lines files contain one object per line rather than a single document — format the lines individually, or wrap them in an array first.
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