JSON Formatter / Validator
③ Data / Text
What it is: JSON is the most common data format for APIs and configs. Expand one-line JSON into a readable layout (or minify it) and check it is valid.
When to use: When an API returns a wall of cramped JSON, or you need to check that JSON is written correctly.
Everything runs locally in your browser — nothing is uploaded.
FAQ
How do I locate a JSON error?
After clicking Format, any syntax error is shown with a message (usually including the position). Common causes are trailing commas, missing quotes, single quotes or comments — none of which standard JSON allows.
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