Developer Tools
JSON Formatter
A JSON formatter and validator. Paste raw API output or a compact payload and get it back as cleanly indented, readable JSON — or minified down to a single line for transport.
Output
How it works
The tool runs JSON.parse on your input. Valid input is re-serialized with your chosen indent width. Invalid input returns the exact character position of the syntax error so you can jump straight to it.
Common ways people use it
- —Inspecting a noisy API response during debugging
- —Validating a hand-written config file before committing
- —Minifying a payload to reduce response size
- —Comparing two JSON blobs by formatting both consistently
Frequently asked questions
Why does my JSON show a "Unexpected token" error?+
Usually a trailing comma, a single quote instead of double, or an unquoted key. Strict JSON requires double-quoted keys and no trailing commas.
Can I format JSON with comments?+
Standard JSON does not allow comments, so a validator will flag them. If you are working with JSONC (JSON with comments), strip the comments before validating.
Is my data sent anywhere?+
No. Parsing and formatting run entirely in your browser, so sensitive payloads never leave your machine.
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