UUID / GUID Generator (v4)
Generate cryptographically secure RFC 4122 version 4 UUIDs (GUIDs) individually or in bulk with custom casing, hyphens toggle, and one-click copy.
How to Use the UUID / GUID Generator (v4)
Select the number of UUIDs you need (1 to 100), configure uppercase/lowercase and hyphens, and click "Generate UUIDs". Identifiers are generated locally using the browser’s Web Crypto API.
Formula & Calculation Method
RFC 4122 / RFC 9562 Version 4 UUID: xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx (where y is 8, 9, a, or b)Uses 122 cryptographically secure random bits with 4 bits fixed for version 4 and 2 bits for the variant.
Calculation Examples
Standard Lowercase with Hyphens
Uppercase without Hyphens
Frequently Asked Questions
Is this UUID generator cryptographically secure?
Yes. UUIDs are generated using the browser’s native crypto.randomUUID() and crypto.getRandomValues() Web APIs, guaranteeing high cryptographic randomness.
What is the difference between a UUID and a GUID?
UUID (Universally Unique Identifier) is the open IETF standard name (RFC 4122 / RFC 9562), whereas GUID (Globally Unique Identifier) is Microsoft’s term for the exact same 128-bit identifier format.