JSON Formatter
Beautify, validate and inspect JSON instantly.
APIs hand you JSON as one endless line. Config files arrive minified. Logs spit out nested objects with no breathing room. This free JSON formatter beautifies pasted JSON with 2 or 4 space indentation, and the validator points at syntax errors with line and column positions instead of a cryptic failure. Common culprits like trailing commas, single quotes, and stray comments get flagged right away. Everything runs in your browser, so API responses with tokens or customer data never leave your machine.
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About JSON Formatter & Validator
APIs hand you JSON as a single endless line. Config files arrive minified. Logs spit out nested objects with no breathing room. Technically it's all valid, and practically, it's unreadable. Formatting restores the structure your eyes need: indentation, line breaks, and nesting you can actually follow.
Paste any JSON and this formatter beautifies it with your choice of 2- or 4-space indentation, or use the validator to check syntax without reformatting. When something's broken, you get the error's line and column position instead of a cryptic failure, which, combined with the most common culprits (trailing commas, single quotes, stray comments), resolves most issues in seconds.
It handles API responses with tokens or customer data. Download the formatted result as a .json file when you need to keep it. One habit worth building: validate every time you hand-edit JSON, before the file goes anywhere. Catching a missing brace here beats debugging a failed deploy later.
How to use JSON Formatter & Validator
- Paste your JSON into the input box.
- Choose 2 or 4 space indentation and click Format.
- Use Validate to check syntax, or fix any reported error and re-run.
- Copy the result or download it as a .json file.
Why use this tool?
- Instant validation with line and column error positions
- Free with no signup or limits
Tips for best results
- Trailing commas are the #1 JSON killer, valid in JavaScript, illegal in JSON. The validator will point at them.
- Use the reported line and column numbers: jump straight there instead of re-reading the whole file.
- Pretty-print before diffing two API responses, diff tools are useless on single-line JSON.
- 2-space indentation keeps wide payloads on screen; 4-space reads better in documentation. Pick one per project.
- Validate after every hand-edit, no matter how small, a single missing quote breaks the entire document.
- JSON has no comments: strip // and /* */ notes before validating, or keep them in a separate doc.