UUID comparison

UUID v4 vs v5 vs v7

Choose the UUID version that matches your data model: random, deterministic, or time-ordered.

Quick answer

Use UUID v4

Use UUID v4 for simple random identifiers when sort order does not matter.

Use UUID v5

Use UUID v5 when the same namespace and name should always produce the same identifier.

Use UUID v7

Use UUID v7 for timestamp-ordered IDs, especially in indexed database columns.

UUID version comparison

Version	Best for	Stable for same input	Sorts by time	Main caveat
UUID v4	Random IDs, public identifiers, general application records.	No	No	Random order can be less friendly for some database indexes.
UUID v5	Repeatable IDs derived from a namespace and a name.	Yes	No	Input changes produce a different UUID.
UUID v7	Time-ordered IDs, logs, events, and database records.	No	Yes	The timestamp portion reveals approximate creation time.

Database storage notes

Store UUIDs in a native UUID column type when your database supports it. Native UUID columns are easier to validate and usually more compact than storing UUID strings.

Practical default

Choose UUID v4 for broad compatibility.
Choose UUID v7 when insert order and index locality matter.
Choose UUID v5 only when deterministic mapping is required.

UUID generators

UUID v4Random identifiers. UUID v5Deterministic name-based identifiers. UUID v7Timestamp-ordered identifiers.