UUID Generator
Random v4 UUIDs, one at a time or up to 100 at once.
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Your files stay on your device
How to use it
A fresh UUID appears as soon as the page loads. Make up to 100 at once, in uppercase or without hyphens, ready to copy. Everything is created on your device.
A UUID is a long random ID, like 3f2a9c1e-8b4d-4e7a-9c2f-1a5b6d8e0f3c, used to label things — database records, files, or devices — without ever getting the same one twice.
One appears as soon as the page opens. Set how many you need, up to 100, and copy them all at once. You can also make them uppercase or remove the hyphens.
Could two ever be the same? In theory, yes. In practice, you’d need to make a billion every second for about 85 years to have even a 50% chance.
FAQ
What kind of UUID is this?
Version 4 — completely random, apart from a few fixed bits. It’s the most common type.
Can two of these ever be the same?
The odds are so tiny that, in practice, no.
Are these UUIDs saved or sent anywhere?
No. They’re made on your device and never sent anywhere.
How it worksFor the curious
A UUID is a 128-bit value written as 32 hex digits in five groups. Version 4 fixes a few bits to mark its version and variant and fills the remaining 122 bits with random data. This tool calls crypto.randomUUID(), the browser’s native generator.
With 122 random bits, generating a billion UUIDs per second for about 85 years gives a 50% chance of a single collision, which is why UUIDs work as primary keys or distributed identifiers with no central coordinator.
Uppercase and hyphen options only change how the value is written, not the underlying bits.