JSON formatter/validator · Guide
How to Format JSON Online in Three Steps
Formatting JSON online takes only a few seconds once you know the flow. Here is the exact process, plus the small details that prevent confusing errors.
Step 1 — Paste the raw JSON
Copy the JSON from wherever it lives — an API response, a log file, a config — and paste it into the input area. Whitespace, line breaks and indentation in the source do not matter; the formatter normalizes all of it.
Step 2 — Read the validation result
The formatter parses the input immediately and shows whether it is valid. If it is not, the error message tells you where parsing failed. Fix the highlighted issue — common culprits are trailing commas, comments (which JSON does not allow), and keys wrapped in single quotes instead of double quotes.
Step 3 — Format or minify
Choose your indent width and format the output for reading, or minify it to a compact single line when you need to send it over the wire. Copy the result with one click.
Frequently asked questions
Why does my JSON say invalid when it looks fine?
The usual reasons are a trailing comma after the last item, single quotes instead of double quotes, or JavaScript-style comments. Strict JSON allows none of these.
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