Co-Authored By:

##### Asked by: Beau Steinbrecht

technology and computing databases# What are the chances of a GUID collision?

Last Updated: 9th March, 2020

**GUIDs**, there is a 50%

**chance**of

**collision**after 2.7e18 random

**GUIDs**have beengenerated. That's more than 2.7 million million million. That's alot.

Click to see full answer.

Furthermore, what are the chances of generating the same GUID?

The term **GUID** is generally used by developersworking with Microsoft technologies, while UUID is used everywhereelse. 128-bits is big enough and the generation algorithm is uniqueenough that if 1,000,000,000 **GUIDs** per second were generatedfor 1 year the **probability** of a duplicate would be only50%.

Also, what is GUID used for? A **GUID** (global unique identifier) is a term**used by** Microsoft for a number that its programminggenerates to create a unique identity for an entity such as a Worddocument. **GUIDs** are widely **used in** Microsoft productsto identify interfaces, replica sets, records, and otherobjects.

Also know, how many GUID combinations are there?

Generating**GUID** Trivia: "**There** are 122 random bits (128 - 2 forvariant - 4 for version) so this calculates to 2^122 or5,316,911,983,139,663,491,615,228,241,121,400,000 **possiblecombinations**."

Are GUIDs random?

**GUIDs** are designed to be unique, not**random**. The **GUID** generation algorithm was designedfor uniqueness. It was not designed for randomness or forunpredictability. Indeed, if you look at an earlier discussion, youcan see that so-called Algorithm 1 is non-**random** and totallypredictable.