UUID/GUID Generator

Generate cryptographically secure UUID v4 or time-based UUID v1 values in bulk. Customize layout options and copy instantly.

⚙️ Generator Settings

Quantity to Generate 10

UUID Version

Include Hyphens (e.g. 123e4567-e89b-12d3...) Uppercase Casing (e.g. A-F instead of a-f) Wrap in Curly Braces (e.g. {123e4567-...})

📋 Generated Results

What is a UUID and a GUID?

A **Universally Unique Identifier (UUID)** is a 128-bit number standardized by the Open Software Foundation (OSF) and detailed in RFC 4122. A **Globally Unique Identifier (GUID)** is simply Microsoft's naming for the same 128-bit standard.

Because 128 bits can contain $3.4 \times 10^{38}$ distinct combinations, the mathematical probability of two random UUIDs colliding is virtually zero. This allows remote nodes to generate primary keys for databases without communicating with a centralized coordinator.

UUID v4 vs. UUID v1

Our bulk generator supports the two most popular standards:

UUID v4 (Random): 122 bits of random entropy. The browser uses cryptographic hardware seeds to populate the bits. This is the recommended choice for database primary keys because it doesn't leak any network or machine metadata.
UUID v1 (Time & Node): Computed from a 60-bit Gregorian UTC timestamp combined with a node ID (traditionally the machine's MAC address) and a clock sequence number. This version is sorting-friendly but can leak the generation epoch and a partial hardware signature.

Frequently Asked Questions

A Universally Unique Identifier (UUID) is a 128-bit label used for information in computer systems. Globally Unique Identifier (GUID) is Microsoft's term for the same standard. They are designed to guarantee uniqueness across space and time without requiring a central registration authority.

Our UUID v4 generator uses the browser's native Web Crypto API (crypto.getRandomValues or crypto.randomUUID), which sources entropy directly from the OS. This makes the generated numbers cryptographically secure and virtually impossible to predict.

Yes, you can generate up to 100 UUIDs at a time with a single click and download the complete list as a plain text (.txt) file or copy it straight to your clipboard.