What is a UUID and why use one?
A UUID (Universally Unique Identifier) is a 128-bit value designed to be globally unique, making it ideal for database keys, distributed systems, and identifiers that must not collide across environments.
Common uses for UUID generators
- Generating IDs for database records and API resources.
- Creating anonymous identifiers for logs, tracking, or test data.
- Producing unique IDs quickly while prototyping apps and scripts.
FAQ
What is a UUID v4?
UUID v4 is a randomly-generated 128-bit identifier designed to be extremely unlikely to collide, making it useful for IDs in apps, databases, and distributed systems.
Is this the same as a GUID?
Often, yes—many systems use GUID as another name for UUID (commonly UUID v4).
Does this generator run in the browser?
Yes. UUIDs are generated client-side using crypto.randomUUID() when available, with a fallback generator if needed.
What is “time-based” mode on this page?
It’s a convenient time-based unique ID format (not a true UUID v1). Use UUID v4 when you need a standard UUID.
How many UUIDs can I generate at once?
Up to 100 per click, and the list keeps the most recent 200 for convenience.