UUID Generator
Generate multiple Universally Unique Identifiers (v4) instantly.
About UUID Generator
What is a UUID?
A Universally Unique Identifier (UUID) is a 128-bit number used to identify information in computer systems uniquely. The term Globally Unique Identifier (GUID) is also commonly used in Microsoft ecosystems. When generated according to standard methods, UUIDs are for practical purposes unique, without depending on a central registration authority or coordination between the parties generating them.
Understanding UUID Version 4
There are several versions of UUIDs (v1 through v5). This generator explicitly creates UUID Version 4. Unlike version 1 which utilizes your computer's MAC address and current time, UUID v4 is generated entirely using cryptographically secure random or pseudo-random numbers. A standard UUID v4 looks like this: f47ac10b-58cc-4372-a567-0e02b2c3d479.
How to use this UUID Generator:
1. Enter the number of UUIDs you want to generate in the input field (you can generate up to 10,000 at a time).
2. Click the "Generate UUIDs" button.
3. The results will instantly appear in the text box below. Each UUID is placed on a new line.
4. Use the "Copy" icon in the action bar to copy the entire batch to your clipboard for use in your database, code, or testing environments.
Privacy and Security Guarantee
All generation happens via your web browser's local Crypto API. This means no data is transmitted over the internet, and no server logs your generated identifiers, ensuring 100% privacy and security for your systems.
Frequently Asked Questions
Are these UUIDs really unique?
Yes. UUID v4 generates 122 bits of randomness. The total number of possible UUID v4s is 2^122 (approximately 5.3 × 10^36). The probability of generating a duplicate (a collision) is so infinitesimally small that it is mathematically negligible. For context, you would need to generate 1 billion UUIDs per second for 85 years to reach a 50% chance of a single collision.
What is the difference between a UUID and a GUID?
In practice, there is no structural difference. UUID (Universally Unique Identifier) is the standard terminology used by the IETF (Internet Engineering Task Force), while GUID (Globally Unique Identifier) is the terminology historically popularized by Microsoft. They both refer to the exact same 128-bit identifier format.
Can I use these UUIDs for primary keys in my database?
Absolutely. UUIDs are widely used as primary keys in databases like PostgreSQL, MySQL, and MongoDB. They are particularly beneficial in distributed architectures (like microservices) because any node can independently generate an ID without needing to contact a central server to increment a counter, thereby preventing database bottlenecks.
How is the random number generation handled?
Our tool uses the standard uuid library combined with the modern Web Crypto API (crypto.getRandomValues). This ensures that the generated numbers are cryptographically secure, overcoming the predictability flaws found in older functions like Math.random().