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JSON Formatter

Beautify, minify, and validate JSON instantly, with readable errors and an optional auto-fix.

Paste JSON to get started

Input

Output

How to use

How to format JSON

Beautify, minify, or validate JSON locally, your data never leaves your browser.

  1. Paste your JSON. Paste or type JSON into the input panel. It is validated as you type.
  2. Beautify or minify. Click Beautify for readable, indented output, or Minify to strip whitespace.
  3. Fix errors. If the JSON is invalid, read the error with its line number, or use auto-fix for common mistakes.
  4. Copy the result. Copy the formatted output to your clipboard with one click.

Online JSON formatter that stays on your device

API responses, config files, and webhook payloads are easier to debug when they are indented and validated. Tokitool’s JSON Formatter beautifies, minifies, and surfaces parse errors with line numbers using the browser’s own JSON parser, so tokens and internal payloads never need to be pasted into a random “format JSON online” SaaS.

Beautify, minify, and common mistakes

Beautify when you are reading. Minify when a form or API field expects compact JSON. Trailing commas, single quotes, and comments are not valid JSON even though they show up in configs. Auto-fix helps with some of those slips; it will not turn JavaScript object literals into strict JSON every time. Fix the error line the parser points at, then beautify again.

What this page is not

  • Not a full IDE. Huge multi-megabyte dumps can slow the tab; use a local editor for those.
  • Not a schema validator (OpenAPI / JSON Schema). It checks parseability, not business rules.
  • Not a place to paste production secrets into a third-party cloud. Processing stays here.

Looking to convert between formats? Try our CSV ↔ JSON Converter for spreadsheet exports and API arrays. Pair with the Base64 Encoder / Decoder when a string is wrapped in Base64, or the Unix Timestamp Converter when epoch fields need a human date. For chat archives instead of JSON, see WhatsApp Chat to PDF.

JSON formatter FAQ

Beautify vs minify

Beautify pretty-prints with indentation so humans can read APIs and configs. Minify strips insignificant whitespace for smaller payloads or paste targets that expect compact JSON.

Where do errors point?

Invalid JSON surfaces a readable message with a line number when the parser can locate it. Fix the highlighted input and beautify again.

Does anything leave my machine?

No. Formatting and validation use the browser’s JSON parser only, useful when pasting secrets or internal payloads you should not send to an online formatter.

Can it fix trailing commas?

Auto-fix helps with some common mistakes. Strict JSON still rejects trailing commas, remove them or convert to a format that allows them outside this tool.

Is there a file size limit?

Very large documents may slow the tab because everything runs in-browser. For huge logs, prefer a local editor; this tool shines for everyday API and config snippets.