JSON Formatter
Format, validate, minify, and sort JSON — fully in your browser.
100% private
This tool runs entirely in your browser. Your input never leaves your device — no uploads, no tracking, no accounts.
Related tools
Base64 Encoder / Decoder
Encode text or files to Base64, or decode Base64 back to text — UTF-8 safe, with URL-safe variant and live byte counter. 100% private.
Developer
Hash Generator
Generate SHA-1, SHA-256, SHA-384, and SHA-512 hashes from text or files, with hex and Base64 output. Uses Web Crypto — 100% private.
Developer
URL Encoder / Decoder
Encode URLs or components for safe transmission, or decode percent-encoded URLs back to plain text. UTF-8 safe.
Developer
UUID Generator
Generate RFC 4122 v4 UUIDs in bulk, with optional hyphens, uppercase, and prefix options. Uses crypto.randomUUID — 100% private.
Developer
About JSON Formatter
Format, validate, minify, and sort JSON — fully in your browser.
How to use
- Enter your input in the tool above.
- Adjust any options (indent, format, etc.) to your preference.
- Use the Copy or Download buttons to save the result.
- Everything happens locally — your data never leaves your browser.
Frequently asked questions
- Is my JSON uploaded anywhere?
- No. All processing happens locally in your browser. Your data never leaves your device.
- What's the max size?
- Large inputs (over 100KB) are processed in a background Web Worker so the UI stays responsive. There is no hard limit — your device's memory is the only ceiling.
- Does this support JSONC (JSON with comments)?
- Not yet. The formatter accepts strict JSON only. Comments and trailing commas will be reported as syntax errors with line and column.