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UUID Generator

Generate RFC 4122 v4 UUIDs in bulk, with optional hyphens, uppercase, and prefix options. Uses crypto.randomUUID — 100% private.

100% private

This tool runs entirely in your browser. Your input never leaves your device — no uploads, no tracking, no accounts.

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About UUID Generator

Generate RFC 4122 v4 UUIDs in bulk, with optional hyphens, uppercase, and prefix options. Uses crypto.randomUUID — 100% private.

How to use

  1. Enter your input in the tool above.
  2. Adjust any options (indent, format, etc.) to your preference.
  3. Use the Copy or Download buttons to save the result.
  4. Everything happens locally — your data never leaves your browser.

Frequently asked questions

What is a UUID?
A Universally Unique Identifier (UUID) is a 128-bit number typically displayed as 32 hex digits in 8-4-4-4-12 format (e.g. 550e8400-e29b-41d4-a716-446655440000). RFC 4122 defines the standard.
How random are these UUIDs?
This tool uses the browser's crypto.randomUUID() API, which generates version-4 UUIDs using a cryptographically secure random number generator. The 122 random bits give ~5.3×10^36 possible UUIDs — collisions are astronomically unlikely.
Are these safe to use as database primary keys?
Yes. UUID v4 is the most common choice for distributed primary keys because no coordination is needed between generators. The trade-off vs sequential IDs is index fragmentation — if that's a concern, consider UUID v7 (time-ordered), which we may add in a future update.