Learn More About UUIDs
Understand UUID versions and when to use each:
About UUID/GUID Generator
A UUID (Universally Unique Identifier) or GUID (Globally Unique Identifier) is a 128-bit number used to identify information in computer systems. Our free online tool generates valid, random UUIDs instantly.
How It Works
The tool uses your browser's secure cryptographic API (crypto.randomUUID() or crypto.getRandomValues()) to generate Version 4 UUIDs. These are randomly generated and have an extremely low probability of collision.
Common Use Cases
- Generating unique primary keys for database records
- Creating unique session IDs or transaction IDs
- Naming uploaded files to prevent overwriting
- Generating unique identifiers for distributed systems
Frequently Asked Questions
Practically nothing. UUID is the standard term used across most platforms, while GUID is Microsoft's implementation of the UUID standard. They are formatted exactly the same way.
While theoretically possible, the chances of generating the same Version 4 UUID twice are astronomically low—so low that it is considered practically impossible.