Is this UUID generator free?

Yes. It is free with no sign-up. Generate one UUID v4 or a bulk list of up to 100, with uppercase and hyphen options, and copy one or copy all.

Can two generated UUIDs ever be the same?

A version 4 UUID carries 122 random bits, so a duplicate is astronomically unlikely — you would need to generate an enormous number before a collision became plausible. It is not mathematically impossible, and this page does not promise otherwise.

Why only version 4? What about version 1?

Version 4 is purely random, which is what most databases, APIs and tests need. Version 1 embeds time and machine-style identifiers that can leak information, so this tool deliberately does not generate it.

Are my UUIDs uploaded or stored?

No. UUIDs are generated on your device with the Web Crypto API (crypto.randomUUID, with a crypto.getRandomValues fallback). Nothing is uploaded, stored on a server or shared, and closing the tab forgets everything.

Can I use a UUID as a password or secret token?

No. A UUID is an identifier, not a secret. Use a password generator and a reputable password manager for credentials, and proper token systems for security-sensitive values.

Generatore UUID — UUID v4 gratis, in blocco e copia

Generatore UUID gratuito. Crea UUID v4 in blocco (fino a 100) con maiuscole e trattini opzionali; copia uno o tutti. 100% locale con Web Crypto: nessun upload, nessuna registrazione.