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Utilnivo

Developer

Utilnivo

JSON Pretty Print Online

Pretty-print JSON with readable indentation directly on your device.

No registration
  • On your device

Browse more in Developer or all tools.

Why is my JSON invalid?

Common causes: trailing commas after the last property, single-quoted strings instead of double quotes, unescaped line breaks inside strings, and comments (JSON does not allow // or /* */). The formatter highlights the parse error line when the browser reports a position—fix that token first, then re-validate.

Private on your device

Your information stays on your device and is not uploaded.

Related tools

This JSON pretty print online tool transforms minified or messy JSON into clean, indented output. Paste API responses, config files, or log extracts and get human-readable structure instantly—no install, no server upload.

Pretty printing adds whitespace only—it does not change parsed values. Use it for code review, support tickets, and documentation samples.

Large payloads may slow the browser; split huge log files before pretty printing.

How to use this tool

Paste JSON into the editor and click format or pretty print. Fix syntax errors if shown, then copy the indented result.

Worked example

Example: pretty-print a single-line webhook payload to spot which nested field triggered a validation error before redeploying.

When to use this

  • Reading minified API responses in DevTools.
  • Preparing JSON examples for README or wiki pages.
  • Debugging config files before deployment.

Common examples

  • Minified API response from `curl` → indented JSON for diffing against staging.
  • Invalid trailing comma in config JSON → parser error line highlighted before deploy.
  • Large nested object → collapse sections mentally after pretty-print for code review.
  • Stripe webhook payload → pretty-print to inspect nested `data.object` fields.
  • package-lock fragment → validate structure before pasting into a bug report.

Common mistakes

  • Expecting pretty print to fix invalid JSON syntax.
  • Pasting secrets into screenshots after formatting.
  • Formatting JavaScript object literals with unquoted keys—they are not valid JSON.

How it works

Paste JSON to format it with readable indentation or minify it into a single line. Invalid JSON shows a parse error with line and column when available. Optional key sorting orders object keys alphabetically. Formatting works on your device.

Limitations

Invalid JSON will not format until syntax errors are fixed. Very large documents may slow the browser tab.

Privacy and file handling

Your data stays on your device and is not uploaded.

Related JSON Formatter pages

These pages use the same json formatter with examples tailored to different tasks.

FAQ

Frequently asked questions

Does pretty printing change my data?

No. Only whitespace and line breaks change—the parsed JSON values stay identical.

Is my JSON sent to a server?

Formatting works on your device for standard Utilnivo JSON tools.

Can I choose indent size?

Use the formatter controls on the tool page for spacing options when available.

Related pages

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