UUID Generator
Cryptographically random v4 UUIDs — one or a thousand at a time, formatted your way.
About this tool
A UUID (universally unique identifier, also called a GUID) is a 128-bit value like 3f9a2c1e-8b4d-4e6f-9a1b-2c3d4e5f6a7b whose randomness makes collisions practically impossible — which is why they're used for database keys, request IDs, file names and API tokens. This generator produces version 4 UUIDs using your browser's cryptographically secure random source.
Generate up to 1,000 at once, switch to UPPERCASE if your codebase prefers it, or strip the hyphens for systems that store the bare 32 hex characters. Copy the whole list with one click — each value is on its own line, ready to paste into code, a spreadsheet or a database seed.
Frequently asked questions
What is a UUID v4?
A universally unique identifier whose 122 random bits make collisions practically impossible — you could generate billions per second for decades without a duplicate. Version 4 means the value is purely random rather than derived from time or hardware.
Are these UUIDs cryptographically random?
Yes — they come from your browser's crypto.randomUUID / crypto.getRandomValues, the same secure randomness source used for encryption keys, not the predictable Math.random().
Is a GUID the same thing as a UUID?
Yes. GUID is Microsoft's name for the same 128-bit identifier format; the values generated here work anywhere either term is used.
Can anyone see the UUIDs I generate?
No — generation happens locally in your browser tab and nothing is transmitted. Refreshing the page leaves no trace of previous values.
Should IDs in my database be UUIDs?
UUIDs are great when IDs are created on many machines at once or must be unguessable. For single-database auto-increment scenarios, sequential integers index faster — many systems use both.