UUID Generator
UUIDs
About
A UUID is a 128-bit identifier written as 8-4-4-4-12 hexadecimal characters. Version 4 is entirely random, while version 7 (RFC 9562) begins with a millisecond Unix timestamp so IDs sort by creation time. Either kind can be created anywhere without a central ID coordinator.
How to use
1.
Under Version, choose v4 (random) or v7 (time-ordered), and set the Count from 1 to 100
2.
A new batch appears as soon as you change an option - select Regenerate for a fresh one
3.
Select Copy to copy every UUID at once, one per line
Common uses
▸
Generating unique IDs for database records during development
▸
Creating placeholder IDs for test fixtures or mock data
▸
Producing unique identifiers for distributed systems
Similar tools
Frequently asked questions
Are generated UUIDs truly unique?
Version 4 UUIDs contain 122 random bits. Version 7 UUIDs contain a millisecond timestamp, 62 random bits and a randomly seeded counter. Either way, the probability of two UUIDs colliding is negligible for any practical application.
Should I use UUID v4 or v7?
Use v7 for database primary keys and anything you want sorted by creation time: newer IDs sort after older ones, so they append to an index instead of landing at random positions in it. Use v4 when an ID must not reveal when it was made - anyone can read the creation time from a v7 UUID.
Is my data sent to a server?
UUID generation runs entirely in your browser using the Web Crypto API. No data is transmitted anywhere.
Can I generate multiple UUIDs at once?
Use the slider or type a count to generate up to 100 UUIDs at once, then copy them all with one click. A batch of v7 UUIDs comes out in ascending order, because IDs created in the same millisecond carry an incrementing counter.
Where are UUIDs commonly used?
UUIDs are used as primary keys in databases, identifiers for API resources, correlation IDs for distributed tracing, and anywhere a unique identifier is needed without a central authority.