Are these UUIDs random enough to be unique?

Yes. They come from the browser's crypto.randomUUID (or crypto.getRandomValues as a fallback), which is a cryptographically secure random source. A version 4 UUID has 122 random bits, so the odds of a collision are negligible for any realistic number of IDs.

What is a version 4 UUID?

It is a 128-bit identifier where almost every bit is random, apart from a few fixed bits that mark it as version 4. It is the format you want when you just need a unique ID and do not need it to encode a timestamp or MAC address.

Is anything sent to a server?

No. Generation happens entirely in your browser. No UUID you create here is ever transmitted or stored anywhere, so it is safe to generate IDs for private systems.

Can I generate them in bulk?

Yes — set the count up to 1000 and copy them all at once. Use the toggles to switch case, add braces, or drop the hyphens to match the format your database or language expects.

UUID Generator

Generate random version 4 UUIDs one at a time or in bulk. Everything happens in your browser — nothing is logged.

How many

HyphensUppercaseBraces { }

5 UUIDs

1960ec57-2003-4ed7-b2c8-943009333c7a
eee6f407-c0e0-461f-ab4e-272b9df49212
31bfaa4e-935b-49f3-abac-a1bc947fd789
410469a6-c560-4d6d-a398-2906fea0fe36
6e9498d1-0187-4bd1-81e4-811546d89fcf

Processed on your device. This file is never uploaded.

1Choose how many UUIDs you need.
2Toggle case, hyphens or braces to match your format.
3Click Generate and copy them all.

Where UUIDs come from here

Every UUID on this page is produced by your browser's built-in cryptographic random number generator — the same source used for security-sensitive work. There is no server involved and no shared sequence, so two people generating IDs at the same moment will not clash.

When to reach for a v4 UUID

Version 4 is the right default when you need a unique identifier and nothing more: primary keys, request IDs, idempotency keys, file names. If you specifically need IDs that sort by creation time you would want a time-based scheme instead, but for the common case — "give me something unique" — v4 is exactly it.

Frequently asked questions

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UUID Generator

Where UUIDs come from here

When to reach for a v4 UUID

Frequently asked questions

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