JSON formatter + validator
Paste JSON, get pretty-printed and validated output — with precise line/column on every error.
{
"name": "Acme",
"founded": 2018,
"metrics": {
"users": 12500,
"growth": 0.42
},
"products": [
"pro",
"enterprise"
],
"active": true
}Three things this tool does
- Format — pretty-print messy JSON with 2-space, 4-space, or tab indent. Useful for reading API responses, debugging structured-data output, or dropping clean JSON into documentation.
- Minify — strip all whitespace for production payloads. Surfaces the byte savings so you know whether it's worth the (modest) win.
- Sort keys — alphabetize keys recursively. Useful for diff-friendly JSON, deterministic test fixtures, and consistent schema markup.
Why precise error positions matter
The native JSON.parse error in your browser console looks like Unexpected token } in JSON at position 247. Technically correct, almost useless when you're looking at a 200-line file. This tool converts that position into a line and column number so you know exactly where to look — usually a missing comma or trailing comma three lines above what the error message points at.
Where this fits in the SEO workflow
If you're using our schema markup generator to produce structured data and want to confirm it's valid before pasting into your <head>, run it through here first. Same goes for any JSON-LD you copy from a competitor or Google Search Console's Rich Results test — formatting it cleanly makes the structure easier to skim and fix.
FAQ
What's the difference between formatting and minifying?
Format produces human-readable JSON with indentation and line breaks. Minify produces machine-readable JSON with no whitespace at all. Use format when you're reading or editing; use minify when you're shipping to production and want the smallest possible payload.
Will sorting keys break anything?
JSON object key order is technically not significant — most tools and APIs treat objects as unordered. But some legacy tools and JSON-Schema validators do rely on key order. If your downstream consumer is one of those, don't sort.
Can it handle JSON with comments or trailing commas?
No. Strict JSON doesn't allow either. The tool uses native JSON.parse which rejects both. If you have JSONC (JSON with Comments) or JSON5, strip the comments and trailing commas first — most editors have a 'minify' or 'format' command that handles it.
Is the input or output saved anywhere?
No. Everything runs in your browser. The text never leaves the page — that's why there's no rate limit or signup gate.
Why does sorting take longer on big JSON?
Sorting keys is recursive — every nested object is alphabetized. For a 10MB JSON file with deep nesting, that's a lot of work. Most JSON formatters skip sorting; we include it because it's actually useful for diff-friendly schema markup.
Can I use this for JSON-LD schema markup validation?
It validates that the JSON parses, but not that the schema.org types and properties are correct. For schema.org-specific validation, use Google's Rich Results Test after copying the formatted output here.
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