Skip to content
TodayHelp Calculators

UUID generator

Ready

Generate up to 100 random version 4 UUIDs in your browser, in upper or lower case, with or without hyphens or braces, and check whether a value is a valid UUID.

How to use

  1. Choose how many UUIDs you need (1–100) and the format options.
  2. Press generate and copy them all with one click.
  3. Paste any value into the checker to see whether it’s a UUID and which version it is.

Formula

  • UUID v4 = 122 random bits + version (4) and variant bits, written as 32 hexadecimal digits in 8-4-4-4-12 groups

Worked example

Example: 0f8fad5b-d9cb-469f-a165-70867728950e

FAQ

Can two UUIDs ever clash?

In practice, no. A v4 UUID has 122 random bits; you would need to generate billions per second for many years before a collision became likely.

Are they sent to your server?

No. They’re generated in your browser with the Web Crypto API (crypto.randomUUID or getRandomValues) and never leave your device.

Related tools