UUID Generator

Looking for a random UUID for your PHP, Python, or JavaScript application? Our free-to-use UUID generator is here to help! Get hassle-free RFC 4122 compliant UUID v4 generation on page load, and with just one click, create a brand new unique identifier. It's perfect for quickly generating UUIDs whenever you need them.

What does UUID stand for?

UUID stands for Universally Unique Identifier.

What are UUIDs?

UUIDs are unique identifiers used to identify information without requiring centralised systems for their generation. They serve as a reliable means to ensure uniqueness across various systems and platforms. When dealing with cross-system environments or when seeking to surpass the limitations of simple auto-incrementing processes in databases, UUIDs offer a way to achieve global uniqueness for data, regardless of the system or programming language employed. UUIDs are a popular choice in system and web application development, especially when working with other external systems. They enable seamless and unambiguous communication between different systems, fostering interoperability and data integrity.

What is the UUID length?

The length of a UUID is 36 characters when represented as a string. A standard UUID is typically composed of 32 hexadecimal digits, which are from a 128-bit value. The UUID format consists of five grouped sections separated by hyphens, with the hyphens added to enhance readability.

What are UUID used for?

UUIDs are used to generate unique identifiers across various systems and programming languages, ensuring that conflicts between different entities are avoided. They are generated using a compliant algorithm (RFC 4122), which allows them to be created concurrently and independently on different systems. The uniqueness provided by UUIDs is crucial for databases like MySQL and is frequently employed in PHP including libraries such as Doctrine. A benefit of using UUID in your PHP applications is if you are required to display the UUID to a user, there is a lower risk that this type of ID is susceptible to username enumeration attacks. Instead of traditionally displaying (in most common cases in the URL) the ID isn't a database sequence, such as "/user/edit/10". Because UUIDs do not reveal any information about the order of creation or the total number of records there is a level of security through obscurity compared to database sequence numbers.

GUID vs UUID

GUID and UUID are essentially the same thing, using the same process to generate unique identifiers. UUID is the more general and widely used term, while GUID is predominantly associated with Microsoft technologies.

UUID versions

The UUID standard includes different versions, ranging from 1 to 5. Among them, version 4 is the most popular globally. While version 1 is also common, it follows a time-based principle and is used less nowadays due to the potential exposure of the MAC address of the system used to generate the UUID. Version 4 addresses this concern by employing a set of random numbers, providing a high likelihood of uniqueness without revealing sensitive information. As a result, version 4 is the most widely adopted version of UUID and is used in many popular programming languages and frameworks.