About this tool
This tool is for developers who need unique identifiers for database records, API keys, test data or distributed systems — a version 4 UUID is generated almost entirely from random bits, making collisions astronomically unlikely even across billions of IDs.
How to use it
- Set how many UUIDs you need.
- Choose whether you want uppercase letters and whether to include hyphens.
- Click "Generate," then copy one or all of the results.
Frequently asked questions
What's the difference between UUID versions?
This tool generates version 4 UUIDs, which are based on random numbers — the most commonly used version for general-purpose unique IDs. Other versions incorporate timestamps or namespace hashing for specific use cases.
How likely is a collision between two generated UUIDs?
Astronomically unlikely — with 122 random bits, you'd need to generate roughly a billion UUIDs per second for about 85 years before even a 50% chance of one collision.
Are these UUIDs sent to a server?
No — they're generated entirely in your browser using the Web Crypto API. Nothing is uploaded or logged.