Question 1

What is a UUID?

Accepted Answer

A UUID (Universally Unique Identifier) is a 128-bit label used to uniquely identify objects in computer systems. Formatted as 32 hexadecimal digits in the pattern xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx, they are designed to be globally unique without a central authority.

Question 2

What is UUID v4?

Accepted Answer

UUID v4 is the most common UUID version, generated from random or pseudo-random numbers. The "4" in position 13 identifies the version, and the variant bits in position 17 identify it as RFC 4122 compliant. The collision probability is so low it is effectively zero.

Question 3

Can I use UUIDs as database primary keys?

Accepted Answer

Yes. UUIDs are commonly used as primary keys in distributed systems because they can be generated independently on any machine without risk of collision. The trade-off is slightly larger storage size (36 chars as text, 16 bytes as binary) compared to auto-increment integers.

Question 4

Are the generated UUIDs truly random?

Accepted Answer

Yes. This tool uses the browser's built-in crypto.randomUUID() Web Crypto API, which generates cryptographically strong random UUIDs. No data is sent to any server.

UUID v4 Generator

Generate UUID v4

About UUID v4