Toolcedar

UUID Generator

Generate random UUID v4 identifiers instantly in your browser. Create one or thousands at once, then copy them with a single click.

Format options

How to use the UUID Generator

  1. Choose how many. Set the number of UUIDs you need, from 1 up to 1,000.
  2. Pick a format. Switch to uppercase or strip the hyphens if your system expects a different shape.
  3. Copy. Copy the whole list to your clipboard with one click.

Frequently asked questions

What is a UUID?
A UUID is a 128-bit identifier designed to be unique without any central authority handing out numbers. Version 4 UUIDs get that uniqueness from randomness rather than from a timestamp or a machine address.
Are these UUIDs generated on your server?
No. They are generated locally by your browser using the Web Crypto API. Nothing is sent over the network, so no identifier you see here ever leaves your device.
How likely is a UUID v4 collision?
A version 4 UUID has 122 random bits. You would need to generate billions of UUIDs per second for a century before a collision became likely, which is why they are safe to create independently on many machines at once.
Can I use a UUID as a database primary key?
Yes, and it is common practice when identifiers must be created by clients or across several services. Be aware that random UUIDs scatter writes across a B-tree index, so high-write tables sometimes prefer a time-sortable identifier instead.

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