Free UUID Generator
Generate UUIDs in bulk. Choose v4 (cryptographically random, the most common) or v7 (timestamp-sortable, ideal for database keys). Copy all or one at a time.
5 v4 randoms
- 1.
96fd7d63-f82d-48df-8b4e-7fa05fc49ba1 - 2.
d6e6ebfd-2a63-455e-9ddd-96917e0e3400 - 3.
f739ed3f-ebaa-442a-81b7-68ae3b517350 - 4.
651a2b4d-ae63-4d4c-bd25-57942c9cb48a - 5.
47a6b92d-9d1c-4c5c-b165-8a7f4f3c80a5
Inspect a UUID
v4 vs v7 — which to use?
- v4: 122 bits of randomness, no timestamp. Universal default.
- v7: prefixes a millisecond timestamp, then random bits. Sortable in databases — better for primary keys because new rows insert near the end of the index.
- For most APIs and tokens, v4 is fine. If you're choosing a database PK that you also insert as the cluster key, v7 reduces index fragmentation dramatically.