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UUID Generator
Generate version 4 UUIDs instantly, one at a time or in bulk up to 100. Uses your browser's cryptographic random number generator, with one-click copy per UUID.
What the tool does
A UUID (universally unique identifier) is a 128-bit label like 3f6d4a8e-1c2b-4d5e-8f9a-0b1c2d3e4f5a, used for database keys, session IDs and filenames. Version 4 means fully random. This tool generates them with crypto.getRandomValues(), the browser's cryptographic RNG.
Worked example
Click "Generate one" to get something like 9b1deb4d-3b7d-4bad-9bdd-2b0d7b3dcb6d. Set the count to 10 and click Generate for ten at once, then Copy all to paste them into a spreadsheet.
Collision odds
With 122 random bits, the chance of two v4 UUIDs colliding is effectively zero: you would need to generate billions per second for a century to expect one duplicate.
Planning estimate only. Results use the list prices shown and may differ from your actual bill. Terms
Frequently asked questions
What is a UUID?
A 128-bit identifier written as 32 hex digits in five groups, like 123e4567-e89b-12d3-a456-426614174000. It is designed to be unique without a central registry.
What does version 4 mean?
The version digit (the first digit of the third group) tells how the UUID was made. Version 4 means randomly generated, the most common kind for application IDs.
Are these UUIDs cryptographically random?
Yes. They come from crypto.getRandomValues(), the browser's cryptographic random number generator, not Math.random().
Can two UUIDs be the same?
In theory yes, in practice no. With 122 random bits you would need about 2.7 quintillion UUIDs to reach a 50% collision chance.