UUID Generator
Generate RFC-4122 version 4 UUIDs singly or in bulk, using the browser's cryptographic random source.
How to use the UUID Generator
- Choose how many UUIDs you need.
- Generate them.
- Copy one or the whole list.
About the UUID Generator
A version 4 UUID is 122 random bits, which makes collisions so improbable that separate systems can generate identifiers independently without coordination. That is why they are the default for distributed systems and offline-capable clients. They are not sequential, so using one as a clustered primary key can hurt database write performance — a common reason teams reach for UUIDv7 instead.
Frequently asked questions
What is a version 4 UUID?
A 128-bit identifier where 122 bits are random, defined by RFC 4122 — the standard random UUID format.
Can two UUIDs collide?
Theoretically yes, practically no. The probability is negligible even across billions of generated values.
Are these cryptographically random?
Yes, they use the browser's crypto random source rather than Math.random.
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