Skip to content
Calculator Tools
Developer Tools

UUID Generator

Generate version 4 format UUIDs from a seed, so the same seed always gives the same IDs.

Enter values

Change the seed for a different set of UUIDs

Results update as you type.

Result

UUIDs

ce1553ab-af42-43a3-9aeb-445c3a253477 e57003a0-20eb-4371-a8d6-19e9ed760e31 d2fccba8-5eca-4893-8e4c-638928ae6dff 912d3e94-ff3c-47ff-87f8-081e159533e5 0ac052b9-164b-4a15-9563-90905da2f351

These are derived from the seed rather than a random source, so the list is reproducible — change the seed to get a different set.

Generated
5
Format
Version 4 layout, 8-4-4-4-12 hex digits
First UUID
ce1553ab-af42-43a3-9aeb-445c3a253477
Bits of identifier
122

Because they are derived from a seed, these are reproducible identifiers, not cryptographically random ones. Use your platform’s crypto UUID function for security-sensitive identifiers.

About the UUID Generator

Generate version 4 format UUIDs from a seed, so the same seed always gives the same IDs.

Also known as: guid generator, uuid v4, unique id generator, random id generator.

How to use this calculator

  1. Enter seed, how many, case, wrap in braces.
  2. The result updates instantly as you type — press Calculate (or Enter) at any time.
  3. Review the breakdown shown under the main result.
  4. Use Copy result or Share to save the answer or send a link with your inputs.

Formula

SHA-256 of the seed, reformatted into the version 4 UUID layout

Worked example

Using the values pre-filled in the calculator above:

  • Seed: calcularo-2026
  • How many = 5
  • Case: Lowercase
  • Wrap in braces: no

the calculator returns:

  • UUIDs: ce1553ab-af42-43a3-9aeb-445c3a253477 e57003a0-20eb-4371-a8d6-19e9ed760e31 d2fccba8-5eca-4893-8e4c-638928ae6dff 912d3e94-ff3c-47ff-87f8-081e159533e5 0ac052b9-164b-4a15-9563-90905da2f351
  • Generated: 5
  • Format: Version 4 layout, 8-4-4-4-12 hex digits
  • First UUID: ce1553ab-af42-43a3-9aeb-445c3a253477