Question 1

What UUID version does this generate?

Accepted Answer

Version 4 (random) — the most commonly used version, generated with crypto.randomUUID(), built directly into your browser.

Question 2

Is a v4 UUID collision actually possible?

Accepted Answer

Practically no. There are 2^122 possible v4 UUIDs — generating a billion per second for 100 years still leaves a vanishingly small chance of ever seeing a collision.

Question 3

Is crypto.randomUUID() actually random?

Accepted Answer

Yes — it draws from your operating system's cryptographically secure random number generator, unlike Math.random(), which is not safe for anything security-sensitive.

Question 4

What's the difference between UUID and GUID?

Accepted Answer

None functionally — GUID is Microsoft's name for the same 128-bit identifier format defined by the UUID standard (RFC 4122).

Question 5

Will other UUID versions (v1, v5, v7) be added?

Accepted Answer

Possibly — v4 covers the vast majority of use cases (a unique ID with no embedded data), so it's the only version supported for now.

UUID / GUID Generator

Frequently asked questions