JSON5 Formatter
Strict JSON
JSON5 Formatter — Free Online Tool
Formats and validates JSON5 (JSON with comments, trailing commas, unquoted keys, single quotes, hex numbers, Infinity, and NaN) into indented output with syntax error reporting — useful for cleaning up JSON5 config files, linting VS Code settings-style documents, and converting relaxed JSON into strict JSON.
How to use the JSON5 Formatter
- Open the tool above — it runs entirely in your browser, so your input never leaves this page.
- Paste or type your input into the field, then press the relevant button (e.g. Encode / Decode, Generate, or Convert).
- Copy the result from the output area with the copy button orCtrl/Cmd + C.
- No signup, no upload, and no tracking — repeat as often as you need.
Frequently asked questions
Is the JSON5 Formatter free to use?
Yes. The JSON5 Formatter is completely free, with no signup, no ads inside the tool, and no hidden limits.
Does the JSON5 Formatter upload my data?
No. The JSON5 Formatter processes everything locally in your browser. Your input is never sent to a server, so it stays private even on shared devices.
Does the JSON5 Formatter work offline?
After the page loads, the JSON5 Formatter runs entirely in your browser, so it keeps working without a network connection.
Free & private — why use this JSON5 Formatter
The JSON5 Formatter runs 100% client-side in your browser. Your data is never uploaded to a server, no account is required, and the tool is completely free. It works offline once the page has loaded and is part of a growing collection of privacy-first developer utilities.