UUID generator
Generate RFC 4122 UUIDs — v1, v4 and v7 — in bulk.
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About the uuid generator
Generates RFC 4122 identifiers in bulk. Version 4 is pure randomness, version 7 puts a millisecond timestamp in the leading bits so IDs sort chronologically, and version 1 combines a timestamp with a node identifier.
Frequently asked questions
Should I use v4 or v7 for database keys?
v7. Random v4 keys scatter inserts across a B-tree index and fragment it; v7 keys arrive in roughly ascending order, so the index grows at the right edge and stays compact.
Can two UUIDs collide?
A v4 UUID has 122 random bits. You would need to generate about a billion per second for 85 years to reach a one-in-a-billion chance of a single collision.