UID
UUID Generator
Create random version 4 UUIDs.
Ad · Large Rectangle (336×280)
How to use UUID Generator
Create random version 4 UUIDs.
- Press Generate to create RFC 4122 version 4 identifiers from the browser crypto module.
- Press it again for more values — every one is generated locally, never sent to a server.
- Copy the UUIDs into your code or database seed.
Practical note. Version 4 UUIDs are random rather than sequential, so they are safe to generate client-side and use as database keys without coordination.
When you actually reach for this
- You need a unique identifier for a database row, a request, or a filename with negligible collision risk.
- You are writing tests or fixtures and want stable-but-distinct IDs without coordinating a central counter.
Where this tool stops being accurate
- Random (v4) UUIDs are not sequential, so indexing millions of them can cause write hotspots in some databases.
- They are 128 bits of text — fine as keys, but heavier than a 64-bit integer if you generate billions.
Frequently asked questions
What does UUID Generator do?
Create random version 4 UUIDs.
v4 vs v1 UUID — which should I use?
Use v4 (random) for privacy and uniqueness without revealing the host; use v1/v7 only when you need time-ordering and accept embedding a MAC/timestamp.
Can two UUIDs ever collide?
Theoretically yes, but at v4's 122 random bits the probability is astronomically low for any realistic volume. Don't build collision handling for it.