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Generate v4 UUIDs.
A UUID (Universally Unique Identifier) is a 128-bit value written as 32 hexadecimal digits in five groups, like 550e8400-e29b-41d4-a716-446655440000. This tool generates version 4 UUIDs, whose bits are almost entirely random.
UUIDs let independent systems create identifiers without a central authority while staying practically guaranteed not to collide — ideal for database keys, request IDs, file names and distributed systems.
In theory yes, but the probability is negligible. With 122 random bits, you could generate 1 billion per second for 85 years and still have only about a 50% chance of a single collision.
Version 4 is random (used here). Version 1 is time and MAC-address based, and versions 3/5 are hashes of a name. Version 4 is the most common when you just need a unique random ID.
They are great for uniqueness and for generating IDs client-side, but their randomness can fragment index locality. Some teams use ordered variants (like UUIDv7) for better database performance.