Helpful Toolbox

UUID Generator

Need a unique ID (or fifty)? Generate random UUIDs and copy them in one go.

📖 How it works & FAQ

What a UUID is for

A UUID (Universally Unique Identifier) is a 128-bit label written as 36 characters — 32 hex digits split into five groups by hyphens, like 3f2504e0-4f89-41d3-9a0c-0305e82c3301. Version 4 UUIDs, the kind this tool makes, are almost entirely random. That randomness is the point: two people generating UUIDs on opposite sides of the world, with no shared database and no coordination, will practically never produce the same one. That lets you mint an ID locally and trust it's unique.

When you'd reach for one

Developers use v4 UUIDs as primary keys in databases, as filenames for uploaded assets, as idempotency keys for API requests, as session or correlation IDs in logs, and as stable identifiers in distributed systems where an auto-incrementing integer would collide or leak how many records exist. They're also handy for test fixtures and seed data when you just need a realistic-looking unique value fast.

How to read a v4 UUID

Look at the 13th character — for a version-4 UUID it's always 4. The 17th character is always 8, 9, a, or b (the variant bits). Everything else is random. Case doesn't matter: A and a are the same value, though lowercase is the common convention.

How to use it

  1. Open the page — a fresh UUID is generated instantly, no button press needed.
  2. Click Copy to put it on your clipboard, or click Generate again for a new one.
  3. To make a batch, enter how many you need and generate the whole list at once.
  4. Select and copy the bulk list, then paste it straight into your code, seed file, or spreadsheet.

FAQ

Can two UUIDs ever collide?
In theory yes, in practice no. A v4 UUID has 122 random bits. You'd need to generate billions per second for many years before a duplicate became likely, so for normal use you can treat them as unique.
Are these UUIDs safe to use as passwords or secret tokens?
They're random enough to be hard to guess, but they aren't a substitute for a purpose-built secret. Use them as identifiers, not as security credentials.
Is anything sent to a server?
No. The UUIDs are generated entirely in your browser using its built-in cryptographic random function — nothing is uploaded or logged.
Is it free?
Yes, completely free and ad-supported, with no signup and no usage limits.