UUID (Universally Unique Identifier) Generator is a free online tool that creates unique IDs widely used in software development. It supports standard UUID v1 (timestamp-based) and v4 (random) used for database keys, session IDs, transaction identifiers, etc.
It increases developer productivity by providing various options such as generating multiple UUIDs in bulk, removing hyphens (-), and converting to uppercase. Use it to instantly generate and copy safe and collision-free identifiers when needed.
Generate cryptographic-quality Universally Unique Identifiers (UUIDs), specifically adhering to the Version 4 standard, for use in distributed software systems and database architecture.
A UUID (Universally Unique Identifier), often called GUID (Globally Unique Identifier) in the Microsoft ecosystem, is a 128-bit number used to identify information in computer systems. Because it is 128 bits long, there are 2^128 possible combinations.
UUIDs come in different versions. Version 1 is generated based on the current time and the MAC address of the computer generating it. While it guarantees uniqueness, it leaks the time of creation and the hardware identity of the creator, which is a privacy concern. This tool generates Version 4 UUIDs, which are based on strong pseudo-random numbers. The format is `xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx`, where the '4' indicates version 4, and 'y' is one of 8, 9, A, or B (identifying the variant).
Is it possible to generate a duplicate? Theoretically, yes. Practically, no. The total number of valid Version 4 UUIDs is approximately 5.3 x 10^36. To put this in perspective: If you generated 1 billion UUIDs every second for the next 85 years, the probability of finding a single duplicate would be about 50%. This "collision resistance" makes UUIDs perfect for generating primary keys in databases that are distributed across multiple servers (sharding) without needing a central authority to coordinate distinct IDs.