UUID Generator Guide
Generate cryptographically unique RFC 4122 Version 4 UUIDs in bulk with uppercase and hyphen toggles.
Overview
Generate cryptographically random RFC 4122 Version 4 UUIDs (GUIDs) individually or in bulk with one-click copy and flexible uppercase and hyphen formatting.
When to Use UUID Generator
Use UUID Generator when you need guaranteed unique identifiers for database records, distributed transactions, or testing payloads without backend code.
Inputs, Formats & Specifications
- Accepted Inputs
- Quantity selector (1 to 100), formatting toggles (uppercase, hyphenless)
- Output Formats
- RFC 4122 Version 4 UUIDs (128-bit identifiers, 36 characters with hyphens)
- Supported Standards
- Standard 8-4-4-4-12 hex string (`xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx`)
- Browser Limits & Scope
- Generates Version 4 (random) UUIDs. Version 1 (MAC address) and Version 5 (namespace SHA-1) are intentionally omitted for privacy and security.
How to use UUID Generator
- Select the quantity of UUIDs to generate (1 to 100).
- Choose your formatting options: Uppercase/lowercase, and with or without hyphens.
- Click Generate to produce fresh, cryptographically unique UUID v4 identifiers.
- Copy single UUIDs or click 'Copy All' to copy the entire batch for database seeding or testing.
Real-World Examples
Frequently Asked Questions
What is the probability of a UUID v4 collision?
Virtually zero. With 122 bits of randomness, you would need to generate approximately 2.71 quintillion UUIDs before having a one-in-a-billion chance of a duplicate.
Are these UUIDs suitable for production databases?
Yes. These are standard RFC 4122 Version 4 UUIDs identical to those produced by PostgreSQL, MongoDB, Node.js `crypto`, and Python `uuid.uuid4()`.
What is the difference between a UUID and a GUID?
UUID (Universally Unique Identifier) is the open IETF standard name, while GUID (Globally Unique Identifier) is Microsoft's implementation term. They refer to the exact same 128-bit structure.
Privacy & Data Security
UUID Generator is designed to run in the browser. Review outputs before sharing them with any external service or workflow.