Format, Validate, Beautify & Minify JSON Online
The best free JSON formatter and validator for developers. Format JSON, validate syntax, beautify, minify, debug, and view JSON tree. Paste, upload, or drop a file. Everything runs in your browser — no data leaves your device.
Everything you need to work with JSON
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JSON Beautifier & Minifier
Pretty-print and beautify JSON with 2/4/tab indentation, or minify JSON to the smallest valid representation.
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JSON Validator & Syntax Checker
Validate JSON with precise line and column errors. Lint JSON and get actionable suggestions for trailing commas, unquoted keys, and RFC 8259 compliance.
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JSON Tree View & Explorer
Virtualized JSON tree viewer with expand/collapse, path breadcrumbs, and fast key/value search. Navigate and explore complex JSON structures.
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Two-Way Format Converters
Convert JSON to YAML, XML, and CSV — and back again. Paste a Kubernetes manifest, a spreadsheet export, or a SOAP response and get clean JSON out.
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Typed Code Generation
Generate TypeScript interfaces, Python dataclasses, Java POJOs, and Go structs (with json tags) straight from a sample API response.
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Detailed JSON Statistics
JSON parser statistics: keys, objects, arrays, depth, characters, lines, file size, and estimated memory footprint.
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JSON Editor & Keyboard Navigation
Full-featured JSON editor with command palette, discoverable shortcuts, keyboard-first operation, and full keyboard navigation from paste to copy.
Why developers pick JSON Formatter Pro
Private & Secure
No backend server for your JSON data — nothing you paste, type, or upload is ever transmitted or collected. Your JSON never leaves your device.
Lightning Fast
JSON parsing runs off the main thread in a Web Worker. Tree view is virtualized for instant loading of large JSON files.
Accessible & Inclusive
WCAG 2.2 AA compliant JSON tool. Keyboard-first, reduced-motion friendly, full accessibility support for all users.
Works Offline
Free JSON formatter that works offline after the first load. No CDNs, no fonts fetched at runtime, fully self-contained.
Frequently asked questions
Is my JSON sent to a server? ＋
No. All parsing, formatting, and validation happens in your browser. The tool has zero backend for user data and no network requests are made with your content.
How do I fix 'Unexpected token' or similar errors? ＋
The status bar shows the exact line, column, and a plain-English suggestion. Common causes are trailing commas, single quotes instead of double quotes, unquoted property names, and stray comments — none of which are permitted by RFC 8259.
Can I use this offline? ＋
Yes. Once the page has loaded, all core functionality — including the editor, worker, and views — runs entirely offline and makes no network requests with your content.
How do I pretty print JSON? ＋
Simply paste or upload your JSON, and our formatter will automatically beautify it with proper indentation. You can choose between 2-space, 4-space, or tab indentation.
Is there a free JSON formatter with no registration needed? ＋
Yes! Our JSON formatter is completely free with no sign-up, registration, or login required. It's also free from ads — we only use anonymous, aggregate analytics to understand site usage.