UUID Generator
Random UUID v4
Settings
Result
Random UUID v4, generated with your browser’s cryptographic randomness.
Values stay in your browser. Nothing is uploaded or stored.
How to use
Generates as many random UUIDs (version 4) as you need, using the browser's cryptographic random generator. The values stay in your browser and are never uploaded or stored.
When to use it
- Primary keys or identifiers for a database.
- File names or request IDs that must not collide.
- Producing test data.
How to use it
- Set how many you want.
- Press generate and they appear.
- Copy a single line, or use copy all.
Good to know
- These are version 4 (random). Unlike version 1, they carry no timestamp or device address, so nothing about where or when they were made leaks.
- The browser's cryptographic random generator is used, which is far harder to predict than ordinary randomness.
- Nothing is stored — refreshing loses them, so copy what you need.
- Every value is produced on this device, not on a server.
Frequently asked questions
Could two of them ever match?
Not zero in theory, but not worth worrying about in practice. A v4 UUID has 122 random bits: generating a billion per second for 85 years gives roughly a 50% chance of a single collision.
What about version 1 or 7?
Only version 4 is offered. Version 1 embeds a timestamp and a device address, which can reveal where and when it was made, and version 7 sorts nicely but exposes the creation time. This is the widely used option that leaks nothing.
Can I use uppercase?
The standard prefers lowercase, and comparisons are case-insensitive. Still, pick one form and keep to it within a system to avoid surprises.
I need a shorter ID.
A UUID is 36 characters, which is long for a URL. People sometimes show only the first eight, but the collision risk rises sharply, so keep the full value as the key and use the short form for display only.