UUID v1 Generator
Generate RFC 4122 version 1 UUIDs (time-based) with a random node.
Generate time-based UUID v1 identifiers. Free, offline, runs in your browser. Read more Show less
What is a UUID v1?
A UUID v1 is a time-based UUID. It contains a 60-bit timestamp (100-nanosecond intervals since 1582-10-15), a 14-bit clock sequence, and a 48-bit node identifier. Traditionally the node is the MAC address of the machine, but this leaks hardware information, so this generator uses a random node with the multicast bit set.
Because the timestamp is part of the UUID, v1 values sort roughly by creation time. They are useful as database keys when you want a UUID but also want approximate ordering.
FAQ
Does this leak my MAC address?
No. The node field is random, with the multicast bit set to indicate it is not a real MAC address.
v1 vs v4 vs v7
v4 is fully random. v1 and v7 embed timestamps; v7 is preferred for new systems because it uses a Unix millisecond timestamp and is lexicographically sortable.
Are these unique?
Yes, with very high probability. The tool uses the browser cryptographic random source for the clock sequence and node.