UUID Generator
Random UUIDs (version 4) plus an inspector for any UUID you paste. Runs entirely in your browser — the random bits come from your own device. ← Workbench
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What you're looking at
A version 4 UUID is just 122 coin flips written in a
structured way: 32 hex digits grouped 8-4-4-4-12, where the 13th digit is
always 4 and the 17th is always 8, 9,
a or b. Those two fixed positions carry no
randomness — they're the labels that say "I'm random" and "I follow the
standard layout", so software can tell v4 apart from time- or name-based
UUIDs.
How unlikely is a collision? If you generated a billion UUIDs per second for a century, the chance of ever producing the same one twice is still comfortably below one in a quadrillion. You can treat every UUID here as unique without a second thought.
The randomness comes from your browser's cryptographic random source — the same generator your operating system uses — so nothing about the value is predictable from anything you've typed or from other UUIDs generated here.