SummaryLog

UUID Generator

Generate random UUID v4 values using the Web Crypto API.

This UUID Generator creates version 4 universally unique identifiers (also called GUIDs) directly in your browser using the Web Crypto API. Each ID is 128 bits of cryptographically strong randomness, so you can safely use them as primary keys, request IDs, file names, or any value that must never collide.

It runs entirely client-side, so nothing you generate is ever sent to a server. Use it when seeding a database, writing tests, building API payloads, or naming resources. You can produce up to 100 UUIDs in one click and switch between lowercase/uppercase or hyphenated/compact formats to match your system.

How to use

  1. Enter how many UUIDs you need in the Count field (1 to 100).
  2. Toggle Uppercase if your system expects capital hex digits, and toggle Hyphens off for a compact 32-character format.
  3. Click Generate to create the list using crypto.randomUUID().
  4. Click Copy next to any single UUID, or Copy All to grab the whole list (one per line).
  5. Click Generate again any time to produce a fresh batch.

FAQ

What version of UUID does this tool generate?
It generates UUID version 4, which is built from random data. Browsers create these with crypto.randomUUID(), a cryptographically secure random source, making accidental collisions effectively impossible.
Is a UUID the same thing as a GUID?
Yes. GUID (Globally Unique Identifier) is the term Microsoft uses, while UUID is the standard name from RFC 4122. The format is identical, so values from this tool work in both contexts.
Are the generated UUIDs sent anywhere?
No. Generation happens entirely in your browser with the Web Crypto API. Nothing is transmitted to a server or logged, so it is safe to use for sensitive identifiers.
Why would I turn off hyphens?
Some databases, file systems, or APIs prefer a compact 32-character hex string without dashes. The Hyphens toggle strips them so you can paste the format your system expects.
Can I generate many UUIDs at once?
Yes, up to 100 per click. Use Copy All to get them as a newline-separated list, which is handy for SQL inserts, fixtures, or seed scripts.