Generate UUIDs
Generated UUIDs
What is a UUID?
A UUID (Universally Unique Identifier) or GUID (Globally Unique Identifier) is a 128-bit number used to identify information in computer systems. The probability of generating duplicate UUIDs is extremely low, making them suitable for distributed systems.
UUID Version 4
This generator creates Version 4 UUIDs, which are randomly generated. They have the format:
Where 'x' is any hexadecimal digit and 'y' is one of 8, 9, A, or B.
Common Uses
- Database primary keys
- Session identifiers
- Transaction IDs
- API keys
- File names to avoid conflicts
- Distributed system identifiers
UUID Collision Probability
The probability of generating duplicate UUIDs is so low that for practical purposes, they can be considered unique. You would need to generate about 1 billion UUIDs per second for 85 years to have a 50% chance of a single collision.
Frequently Asked Questions
What is the difference between UUID and GUID?
UUID (Universally Unique Identifier) and GUID (Globally Unique Identifier) are essentially the same thing. GUID is Microsoft's implementation of UUID. Both are 128-bit identifiers with the same format.
Are UUIDs truly unique?
While not mathematically guaranteed, the probability of duplicate UUIDs is extremely low. Version 4 UUIDs have 122 random bits, making collisions practically impossible in normal use.
Can I use UUIDs as database primary keys?
Yes, UUIDs are commonly used as primary keys. They allow distributed generation without coordination and prevent key collisions when merging databases.
Is this UUID generator secure for passwords?
No, UUIDs are not suitable for passwords. They are designed for uniqueness, not security. Use our Password Generator for creating secure passwords.