UUID Generator

Random UUID

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v4

f78a91df-486d-4adc-b544-feddb7902455

Time based UUID

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v6

1f181dc3-c66e-6300-a623-64e721d2d327

UUID v7

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Time + Random

Uses a 48-bit Unix epoch timestamp (millisecond precision) followed by random bits. Time-sortable and optimized for better database indexing than V1. Considered the modern best practice.

019f7014-b530-76db-96c4-fce058d87d8d

UUID v6

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Reordered Time-based

Time-based like V1 but reorders the bits to be monotonically increasing (better for database indexing). Does not expose the MAC address (often uses a random node ID instead).

1f181dc3-c66e-6301-a9ef-2046fcbf55ef

UUID v4

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Random (Pseudo-random numbers)

Maximum unpredictability and privacy. Not sortable by time. Higher (but still very low) theoretical collision chance compared to time-based.

9e4ea223-5d6a-4c6c-be46-b5c60998cdac

UUID v1

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Time-based + MAC Address

High uniqueness, sortable by time. Privacy concern due to including the generating machine's MAC address.

3c66e302-81dc-11f1-a623-65e721d2d327