UUID Generator

A Universally Unique Identifier (UUID) is a 128-bit number used to uniquely identify information. UUIDs are commonly used as database keys, session IDs, and transaction identifiers.

UUID v1 is time-based (includes timestamp + MAC address), useful for sortable identifiers. UUID v4 is purely random, offering maximum unpredictability - the most commonly used type.

UUID v4 uses 122 random bits (the remaining 6 are reserved for version/variant). With 2^122 possible values, the probability of collision is astronomically small. You'd need to generate 1 billion UUIDs per second for about 100 years to have a 50% chance of a single collision.

UUIDs have a standard structure: version bits (4 bits in position 13) identify the UUID version, and variant bits (2-3 bits in position 17) identify the UUID layout. This ensures every standards-compliant UUID can be identified and processed correctly by any system.

Yes, but with considerations. UUIDs eliminate the need for sequential IDs and work well in distributed systems. However, random UUIDs can cause index fragmentation in B-tree databases like MySQL/PostgreSQL. UUID v7 (time-ordered) addresses this by making UUIDs sortable.

UUID v4 generated by this tool uses crypto.getRandomValues where available, which provides cryptographically strong randomness. UUIDs are not designed as security tokens, but the randomness quality is sufficient for generation purposes.

UUID v4 uses crypto-grade randomness, making collisions astronomically unlikely. You'd need to generate billions of UUIDs per second for decades to have a meaningful collision chance.