UUID Generator

Runs in your browser, nothing is uploaded. Your input is not saved.

Generate random (v4) or time-ordered (v7) UUIDs in bulk.

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About this tool

Version 4 UUIDs are 122 random bits, which makes collisions practically impossible. Version 7 UUIDs start with a millisecond timestamp, so they sort by creation time and keep database indexes more compact than random keys. All values come from your browser’s cryptographic random generator.

Questions

Should I use v4 or v7?

Use v4 when you only need uniqueness. Use v7 for database primary keys, where time-ordered values keep inserts local in the index. v7 reveals the creation time, so avoid it for IDs that must not leak that.

Can two generated UUIDs collide?

With v4 the chance is negligible for any realistic volume. Within a batch, this tool also gives each v7 value a later timestamp than the one before it.

Are these generated on a server?

No. They are created in your browser with crypto.getRandomValues, and nothing is sent anywhere.

Keyboard shortcuts

UUID Generator

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