What UUID version is generated?

Version 4 (random). Each UUID has 122 random bits, generated by the browser's crypto.randomUUID() - the same API used by secure systems, not a Math.random() hack.

In practice, no. With 122 random bits you'd need to generate about a billion UUIDs per second for 85 years to reach a 50% collision chance. For IDs, v4 is effectively unique.

Should I use UUIDs as database primary keys?

They work, but random UUIDs fragment indexes in some databases. If you need sortable IDs, consider UUIDv7 (time-ordered) - this tool generates v4, which is best for tokens, request IDs and test data.

What's the difference between UUID and GUID?

They're the same 128-bit format - GUID is just Microsoft's name for UUID. A v4 UUID works wherever a GUID is expected.

Developer Tools

UUID Generator

Need a batch of IDs for your database seed or test fixtures? Generate hundreds of v4 UUIDs in one click.

How many? (1–1000)

Format

7f2cb1c2-8b01-4308-a475-bcead6ddb9f4
9c467f8d-bfcd-4fc8-b063-2023232d307a
5bed35ed-6d0d-4481-973e-3abeaaf432f1
6ad660d3-748f-4f32-98f5-17154938866c
d618e451-b26e-4c51-a680-bb96dff18fd0
f9772732-fa1e-417e-8dbe-f72779c77e21
b678037a-066e-4ea4-9b8e-bc605e2a40d8
d595dcdd-2305-4d4a-bc2e-7a5995eddd6e
cc4b0061-b955-491f-898d-6a916846056a
fdda4a26-a2b9-4a83-b84d-a9e4c9380a92

Version 4 UUIDs generated with crypto.randomUUID(). Real cryptographic randomness, one per line for easy pasting. Everything happens locally in your browser.

Private by design: This tool runs entirely in your browser. Nothing you type or upload is sent to a server.

How to use UUID Generator

Set the count. Choose how many UUIDs you need - 1 to 1000.
Pick formatting. Toggle uppercase and hyphens to match your system's expected format.
Generate. One click produces the full batch instantly.
Copy. Copy individual UUIDs or grab the whole list with Copy All.

UUID Generator Features

crypto.randomUUID() - real v4 randomness
Bulk generation up to 1000
Uppercase / lowercase toggle
Hyphens on/off
Copy individual or copy-all
One per line for easy pasting

UUID Generator Frequently asked questions

: Version 4 (random). Each UUID has 122 random bits, generated by the browser's crypto.randomUUID() - the same API used by secure systems, not a Math.random() hack.
: In practice, no. With 122 random bits you'd need to generate about a billion UUIDs per second for 85 years to reach a 50% collision chance. For IDs, v4 is effectively unique.
: They work, but random UUIDs fragment indexes in some databases. If you need sortable IDs, consider UUIDv7 (time-ordered) - this tool generates v4, which is best for tokens, request IDs and test data.
: They're the same 128-bit format - GUID is just Microsoft's name for UUID. A v4 UUID works wherever a GUID is expected.

UUID Generator

How to use UUID Generator

UUID Generator Features

UUID Generator Frequently asked questions

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