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UUID generator

Generate multiple Universally Unique Identifiers (UUIDs)

About this tool

This tool allows you to generate one or more universally unique identifiers.

What are Universally Unique Identifiers?

UUIDs are randomly generated IDs which are always unique.

Their uniqueness comes from the fact that there are 1036 possible combinations (that's 1 with 36 zeros on the end).

For comparison, if each UUID was 1 nanometer long, laying them end-to-end would be longer than the observable universe!

What do they look like?

UUIDs are made up of 36 characters (numbers and letters), separated into groups by hyphens.

Example

e11a2531-95b0-409f-bef0-a47eb9d3227a

Benefits of UUIDs

  • They are not assigned by a central authority; anyone can randomly generate one!
  • They are not sequential, so they don't reveal the amount or order of records.
  • They are highly portable compared to numerical identifiers which are often duplicated across systems or data types.

Downsides of UUIDs

  • They are long, and not easy to memorize or copy by hand.
  • Since they are non-sequential, you can't determine creation order.
  • They may be slightly less efficient (compared to integers) when indexing in a database.

Technical specifications

Size
128 bit
Length
36 characters
Base
Base 16 (hexadecimal)
Sequential
No
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