JSON Formatter

When to use JSON Formatter

You're staring at a minified API response pasted into a Slack thread — one 4000-character line with no whitespace — trying to figure out which nested key holds the value that's breaking your integration. Paste it here and JSON.parse + indent turns it into a readable tree with syntax highlighting in under a second. The tool also surfaces the usual gotchas: missing commas, unclosed brackets, trailing commas that Node tolerates but the spec doesn't. Everything runs in your local browser tab, so API keys and OAuth tokens embedded in that response payload never touch a third-party server. Format it, scan the structure, collapse the nested noise, copy the clean version out.

• Untangle a minified webhook body from a PagerDuty alert
• Validate a config file before committing to the repo
• Read a Stripe API response without opening the dashboard

About this tool

Paste messy or minified JSON and get it pretty-printed with proper indentation, syntax highlighting, and instant validation for the usual gotchas: missing commas, unclosed brackets, trailing whitespace, stray BOMs. Useful when you're debugging an API response, cleaning up a config file before committing it, or making sense of a webhook payload someone sent you in a Slack thread. Collapse nested objects to scan the structure without losing your place. Everything runs locally — nothing is uploaded, so API keys embedded in that response token stay off any third-party server. Copy the formatted output and move on.