Everything You Need to Know About UUID v4
What is a UUID v4?
A Version 4 UUID is a 128-bit number composed of 32 hexadecimal characters and 4 hyphens. 122 bits are cryptographically random, providing 5.3 × 1036 unique combinations.
Collision Probability
The chance of generating a duplicate UUID v4 is negligible. You would need to generate 1 billion UUIDs per second for 85 years to have a 50% probability of a single collision.
UUID vs Microsoft GUID
GUID (Globally Unique Identifier) is Microsoft's implementation of the UUID standard. They share the identical 128-bit format. Microsoft tools typically display GUIDs in uppercase with curly braces (e.g., {B7C2A9...}).