Version
How many
Namespace
Namespace UUID
Name
v5 is deterministic — the same namespace + name always yields the same UUID.Output
Identifiers are generated in your browser with the Web Crypto API — nothing is sent anywhere.
Generate UUIDs (v4, v7, v5, nil) and ULIDs in bulk — entirely in your browser.
Identifiers are generated in your browser with the Web Crypto API — nothing is sent anywhere.
v4Random. 122 bits of randomness — the everyday default when you just need a unique value.v7Time-ordered (RFC 9562): a 48-bit Unix-millisecond prefix + random tail, so keys sort by creation time. Great for database primary keys.v5Deterministic. SHA-1 hash of a namespace UUID + a name, so the same input always maps to the same UUID.nilThe all-zero UUID 00000000-0000-0000-0000-000000000000 — a placeholder / "none" value.ULID26-char Crockford base32. A 48-bit timestamp + 80 random bits — lexicographically sortable and URL-friendly.8-4-4-4-12A UUID is 32 hex digits in five hyphenated groups. Toggle Hyphens off for the compact 32-char form.version nibbleThe 13th hex digit encodes the version (4, 7, 5…); the variant bits sit in the 17th. This tool sets both correctly.ULID sortBecause the timestamp leads, two ULIDs created milliseconds apart already sort in creation order as plain strings.