UUID Generator
What Is a UUID?
A UUID (Universally Unique Identifier) is a 128-bit label used to uniquely identify information in computer systems. Also known as GUIDs (Globally Unique Identifiers), UUIDs are formatted as 32 hexadecimal characters displayed in 5 groups separated by hyphens: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx.
UUID Versions
- UUID v4 (Random) — Generated using random or pseudo-random numbers. Most commonly used. Extremely low collision probability (practically zero).
- UUID v1 (Timestamp) — Based on the current timestamp and a node identifier. Guaranteed unique but reveals creation time.
How to Use This Tool
Select the UUID version and count, then click Generate. You can generate up to 100 UUIDs at once. Use the options to control formatting (uppercase, with or without hyphens).
Frequently Asked Questions
Are UUIDs truly unique?
UUID v4 generates random values from a space of 2¹²² possibilities. The probability of a collision is astronomically small — you'd need to generate about 2.71 quintillion UUIDs to have a 50% chance of a single collision.
When should I use UUIDs?
UUIDs are ideal for database primary keys in distributed systems, session identifiers, transaction IDs, and any scenario where you need a unique identifier without coordinating with a central authority.