UUID Generator Guide
A UUID generator produces Universally Unique Identifiers in version 4 format, the 128-bit random IDs used everywhere from database primary keys to distributed system message tags. Each UUID is rendered as 32 hexadecimal digits grouped into five sections separated by hyphens, for example 550e8400-e29b-41d4-a716-446655440000. The randomness is strong enough that collisions are practically impossible, so you can generate IDs on different machines without coordination and trust they will never clash. The generator uses the browser crypto.randomUUID API when available, falling back to getRandomValues to assemble 16 random bytes. Six bits are fixed to mark the version and variant as required by RFC 4122, leaving 122 bits of true randomness. The result is formatted into the canonical 8-4-4-4-12 hyphenated string, and you can generate a single UUID or thousands at once for bulk operations. UUIDs are not secret, so never use them as a substitute for access tokens. Version 4 UUIDs are random, which means they fragment database indexes; consider UUIDv7 if you need time-sortable IDs. Lowercasing or uppercasing a UUID does not change its meaning because hex digits are case-insensitive.