- 1
d8463376-ba27-4df3-87d4-3a50b34f33d4
Encodes the current timestamp plus a random node ID. Values generated within the same millisecond are monotonically incremented. Useful when you need to trace when a record was created.
All significant bits are filled with cryptographically secure random data. The most widely used UUID version — ideal for primary keys, session tokens, and correlation IDs where ordering does not matter.
Embeds a Unix millisecond timestamp in the most-significant bits, making UUIDs sortable by creation time. Dramatically improves database index performance compared to v4. Recommended for new database primary keys.
About
The UUID Generator produces universally unique identifiers (UUIDs) in version 1 (timestamp-based), version 4 (random), and version 7 (sortable, timestamp-based) formats. UUIDs are used as primary keys in databases, session tokens, file names, and anywhere a guaranteed-unique identifier is needed.
How to use
- 1 Select the UUID version (v1, v4, or v7).
- 2 Choose how many UUIDs to generate (1 to 100).
- 3 Click Generate and copy the results to your clipboard.
- 4 Toggle uppercase or lowercase formatting as needed.
- Which UUID version should I use for database primary keys?
- UUID v7 is the best choice for new database primary keys. Its millisecond-precision timestamp prefix makes UUIDs lexicographically sortable by creation time, which dramatically improves B-tree index performance compared to the random v4. If your database or ORM does not yet support v7, v4 is the widely supported fallback.
- Are UUIDs generated in this tool truly unique?
- UUID v4 uses 122 bits of cryptographically secure random data, making collisions statistically impossible in practice — the probability of a collision in 1 billion UUIDs is less than 1 in a billion. UUID v7 uses 74 random bits plus a timestamp prefix, offering similar collision resistance with sortability.
- Can I generate multiple UUIDs at once?
- Yes. Set the count field to any number between 1 and 100 and click Generate to produce a batch. All UUIDs are displayed in a numbered list and can be copied individually or all at once with the Copy All button.