UUID Generator — Frequently Asked Questions
Everything you need to know about using UUID Generator.
What is a UUID v4?
A 128-bit identifier, 122 bits of which are random. It looks like xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx — the 4 marks the version, y is one of 8, 9, a, or b. Effectively unique forever.
Can two UUIDs ever collide?
Mathematically possible, practically never. You would need to generate billions per second for centuries to hit a collision. Safe to use as primary keys without checking for duplicates.
What is the difference between UUID and GUID?
None — GUID is Microsoft’s name for the same standard, often written with braces and uppercase. Pick the format that matches your system’s convention.
Are these UUIDs cryptographically secure?
Yes — we use crypto.randomUUID() and crypto.getRandomValues() under the hood, which pull from the browser’s cryptographic random number generator.
Why is the maximum 1000?
To keep the UI usable. Beyond 1000 you should generate UUIDs in code as needed rather than copy-paste from a web tool.