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UUID Generator

Generate unique identifiers instantly

Methodology & standardsRuns in your browser

Inputs

Results update live

Interpretation

How UUID Generation works

The UUID Generator creates version 4 universally unique identifiers using cryptographic random number generation. Each UUID is a 128-bit value displayed as 32 hexadecimal digits in a 8-4-4-4-12 pattern.

Example

Key features

A realistic scenario showing how the calculation guides a practical decision.

Formula

Format: xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx (where 4 indicates version, y is 8, 9, a, or b)

  • Generate UUID v4 identifiers
  • Bulk generation up to 50 at once
  • Toggle uppercase/lowercase format
  • Option to include or exclude hyphens
  • Copy individual UUIDs or all at once

Watch out

Common mistakes

  • UUID v4 uses random or pseudo-random numbers. The probability of generating a duplicate is astronomically low — roughly 1 in 5.3 x 10^36. UUIDs are commonly used as database primary keys, session identifiers, and distributed system identifiers.