UUID generator
Generate one or many cryptographically random UUID v4 identifiers and copy or download them.
Generate cryptographically random version 4 UUIDs locally. Choose how many you need and copy or download the list.
Standards-shaped
UUID v4 fixes the version and variant bits while leaving 122 random bits.
Browser randomness
Values come from the Web Crypto API, not Math.random.
Frequently asked questions
Are UUIDs guaranteed unique?
No finite random identifier can offer a literal guarantee, but collisions with properly generated UUID v4 values are extraordinarily unlikely.
Are these sent anywhere?
No. Generation and downloads happen locally.
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