Skip to main content

UUID Generator

Generate cryptographically random UUID v4s — one or a thousand — with code-ready formatting.

100% freeRuns in your browserNo signup, no watermark

UUIDs (universally unique identifiers) label database rows, API resources, distributed events, and test fixtures without any central coordination. This generator produces version 4 UUIDs from your browser’s cryptographic random source — crypto.randomUUID, the same quality of randomness your backend would use, not Math.random().

Generate up to 1,000 at once and shape the output for wherever it is going: uppercase for SQL Server, hyphen-less for compact keys, or quoted with trailing commas ready to paste into a code array. A built-in validator reports the version and variant of any UUID you paste. Generation happens locally — no server, no logs, no rate limits.

How to generate UUIDs

  1. 1

    Choose how many UUIDs you need (1–1,000) and click Generate.

  2. 2

    Apply formatting — uppercase, no hyphens, or quoted list — as needed.

  3. 3

    Copy all or download the list as a .txt file.

Why use Nofolo’s uuid generator?

Crypto-grade randomness

Uses crypto.randomUUID / getRandomValues — suitable for real identifiers, unlike Math.random().

Bulk generation

Up to 1,000 UUIDs in one click, ready to copy or download as .txt.

Code-ready formatting

Uppercase, no-hyphen, or quoted-list output for pasting straight into SQL, configs, or arrays.

UUID validator

Paste any UUID to check its format and see its version and variant.

NIL UUID on hand

The all-zeros NIL UUID is one click away for defaults and sentinel values.

Private and offline-friendly

Everything is generated in your browser — nothing is requested from a server.

Frequently asked questions

What is a version 4 UUID?

A UUID whose 122 usable bits are random. The version digit is 4 and the variant bits are 10, giving the familiar xxxxxxxx-xxxx-4xxx-yxxx-… shape where y is 8, 9, a, or b. v4 is the right default when you simply need unique IDs.

Can two generated UUIDs collide?

In practice, no. With 122 random bits you would need to generate about 2.7 quintillion UUIDs to reach even a 50% chance of a single collision. Code defensively, but do not design around it.

Are uppercase UUIDs valid?

Yes. RFC 4122 treats UUIDs as case-insensitive, with lowercase as the canonical output form. Some databases display them uppercase — both parse identically.

Is it safe to use these UUIDs in production?

Yes. They are produced locally by your browser’s cryptographically secure random generator and never transmitted, logged, or stored — this page cannot see or keep them.

What is the NIL UUID?

00000000-0000-0000-0000-000000000000 — the special all-zeros UUID defined by RFC 4122, often used as a placeholder or “no value” sentinel.

Related tools