UUID Generator
Generate UUID v1, v4, and v7 values directly in your browser.
Generated results
Choosing a UUID version
Use v4 for random identifiers and v7 when identifiers benefit from time-ordered sorting. v1 includes time information but this tool uses a random node value instead of your device MAC address.
Match the UUID version to storage behavior
Use v4 when identifiers should be random and ordering is irrelevant. Use v7 when time-ordered values can improve index locality or chronological sorting. This v1 implementation uses a random node value, so it does not expose a device MAC address.
Uniqueness is probabilistic, not absolute
UUIDs provide an extremely large identifier space, but no random scheme can promise that a collision is impossible. Databases should still enforce a unique constraint, and authentication secrets should use a purpose-built random token rather than assuming an identifier is confidential.
Frequently Asked Questions
Are UUIDs sent to a server?
No. Generation happens in your browser, and neither UUIDs nor settings are sent to Utilook.
How do v1, v4, and v7 differ?
v1 is time-based, v4 is random-based, and v7 uses Unix milliseconds to support time-oriented sorting.
Does v1 include my real MAC address?
No. This tool uses a random node value to avoid exposing a device identifier.
Will v7 UUIDs always sort in creation order?
Values created in different milliseconds sort by time. Values created within the same millisecond can sort differently because of their random portion.
How many UUIDs can I generate at once?
You can generate up to 100 UUIDs at once.