UUID Generator
Generate cryptographically secure UUID v4 identifiers using crypto.randomUUID(). Generate up to 50 at once — copy individually or all together.
d8116912-2d55-44da-8087-7accdadbf6b868a46c8b-69c3-443c-b98d-7cc04adff1fd714bb315-9384-471f-bd53-f5ce0bab360e026b9be9-fe45-481a-b388-c80a8849511b99d329c1-d175-439e-856d-ff43b4e6f201UUID v4 — What You Need to Know
UUID v4 uses 122 bits of randomness, giving ~5.3 × 10³⁶ possible values. The probability of a collision when generating 1 billion UUIDs is roughly 1 in 10²³ — effectively zero for any practical use. Safe to use as database primary keys, idempotency keys, session IDs, and trace IDs.crypto.randomUUID() is available in all modern browsers and Node.js 15+.
122 bits of cryptographically random data from crypto.randomUUID() (internally uses crypto.getRandomValues)
Bits 48–51 set to 0100 (hex 4) — identifies this as a version 4 UUID
Bits 64–65 set to 10 binary — marks RFC 4122 / ITU-T X.667 variant
128 bits written as 32 hex characters grouped 8-4-4-4-12 with hyphens: xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx
Spec: RFC 9562 §5.4 (UUID v4), replaces RFC 4122