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What is the best free UUID generator?

Short answer

The best free UUID generator produces cryptographically random v4 UUIDs, one at a time or in bulk, right in your browser with one-click copy. If you need identifiers that sort by creation time, a companion generator produces the newer time-ordered UUID v7 as well, both free with no sign-up.

What to look for in a UUID generator

The two things that matter are randomness quality and bulk output. A v4 UUID is only as good as the random source behind it, so the generator should use the cryptographically secure randomness built into the browser rather than a plain pseudo-random function. And since UUIDs are often needed in batches for seed data and fixtures, generating in bulk with easy copying saves real time.

v4 for randomness, v7 when order matters

The standard generator produces random v4 UUIDs (also called GUIDs), singly or in bulk, generated locally with one-click copy. For database primary keys, the v7 generator produces time-ordered, sortable version-7 UUIDs, which keep inserts roughly sequential and are friendlier to index locality than fully random ids. Both run entirely client-side.

Frequently asked questions

Are the UUIDs cryptographically random?

Yes. v4 UUIDs are generated from the secure random source built into your browser.

Can I generate many at once?

Yes. Both the v4 and v7 generators support bulk generation with easy copying.

When should I use v7 instead of v4?

Use v7 when identifiers should sort by creation time, such as database keys where insertion order and index locality matter.

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