UUID Generator

How to Use the UUID Generator

The UUID Generator creates version 4 (random) Universally Unique Identifiers. UUIDs are 128-bit identifiers formatted as 32 hexadecimal digits in five groups separated by hyphens: xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx.

Generating UUIDs

Select the quantity (1 to 100) and click Generate. Each UUID is created using cryptographically secure random numbers from crypto.getRandomValues(). Version 4 UUIDs have the version digit set to 4 and the variant bits set according to RFC 4122.

UUID Validation

Paste a UUID into the validator input to check if it matches the standard UUID format. The validator checks the correct pattern of hexadecimal characters, hyphens, version digit, and variant bits.

When to Use UUIDs

UUIDs are used as database primary keys, API request identifiers, session tokens, distributed system node IDs, and file identifiers. The probability of generating duplicate v4 UUIDs is astronomically low — you would need to generate 2.71 quintillion UUIDs to have a 50% chance of one collision.

Frequently Asked Questions

Q: Are v4 UUIDs truly unique?

A: While not guaranteed unique, the probability of collision is negligibly small. A v4 UUID has 122 random bits, giving approximately 5.3 x 10^36 possible values.

Q: What is the difference between UUID and GUID?

A: GUID (Globally Unique Identifier) is Microsoft's term for UUID. They are functionally identical. UUID is the standard term defined in RFC 4122.

Q: Can UUIDs be used as security tokens?

A: While v4 UUIDs use cryptographic randomness, they are not designed as security tokens. For authentication tokens, use dedicated libraries that provide additional security properties.