online UUID generator

What is a UUID?

UUID stands for Universally Unique Identifier.

According to Wikipedia, a UUID is a 16-byte (128-bit) number. In its canonical form, a UUID is represented by 32 hexadecimal digits, displayed in five groups separated by hyphens, in the form 8-4-4-4-12 for a total of 36 characters (32 digits and four hyphens).

Example: 550e8400-e29b-41d4-a716-446655440000

How Unique is a UUID?

Pretty darn unique!

There are 340,282,366,920,938,463,463,374,607,431,768,211,456 possible UUIDs (16 to the 32nd power), or about 3 × 1038.

"...after generating 1 billion UUIDs every second for the next 100 years, the probability of creating just one duplicate would be about 50%. The probability of one duplicate would be about 50% if every person on earth owns 600 million UUIDs."
"The total number of unique keys is 2128 or 3.4×1038. This number is so large that the probability of the same number being generated randomly twice is negligible; however, UUID numbers are not always generated randomly."

What are UUIDs used for?

If you're at this page, you probably already know, but - in case you were searching for UUID (Ultimate Urinal Interior Decorators), and found this instead, this is for you.

UUIDs are idenfication numbers used in the computer / programming industry often as the primiary key of a database table. Confused? How about in simpler terms: It's a VERY unique number that computer geeks (and proud of it!) use to make sure their geeky data doesn't get mixed up with other geeky data.

What's the difference between a UUID and a GUID?

A GUID (Globally unique identifier) is usually synonymous with UUID, but can also refer to Microsoft's version of a UUID.