Your data is never sent to any server.
The JSON formatter and validator beautifies, indents, minifies and validates JSON instantly. Paste your data, choose the indentation and copy the result; if the JSON is invalid, the tool tells you exactly what’s wrong.
Everything happens in your browser, with nothing sent to any server.
What it’s for
- Debugging APIs: turn a compact API response into readable, indented JSON.
- Validation: catch syntax errors before shipping a config file or payload.
- Minifying: shrink JSON to its smallest form for storage or transfer.
- Cleaning up: fix trailing commas and quoting issues in hand-written JSON.
How to use JSON Formatter
- 1
Paste your JSON
Type or paste the JSON into the input pane. You can paste straight from an API response, a file or a log.
- 2
Choose the indentation
Pick 2, 3 or 4 spaces to beautify, or “Compact” to minify into a single line.
- 3
Fix errors automatically (optional)
Enable “Fix JSON” to repair common mistakes like trailing commas or missing quotes before formatting.
- 4
Copy the result
Press the copy button to send the formatted JSON to your clipboard. Everything happens in your browser.
Frequently asked questions
Is my JSON sent to any server?
No. Parsing, validation and formatting all run in your browser, so it is safe to paste internal or sensitive data.
What does the validator detect?
Syntax errors such as unclosed brackets, trailing commas, unquoted keys or invalid values, with a message describing the problem.
What does "Fix JSON" do?
It tries to repair frequent mistakes (trailing commas, single quotes, missing quotes) so almost-valid JSON can still be formatted.
What is the difference between beautify and minify?
Beautify adds indentation and line breaks for readability; minify removes all unnecessary whitespace to produce the smallest possible output.
Is there a size limit?
No artificial limit. Everything is processed locally, so performance depends only on your device.