UUIDs, also known as "universally unique IDs" or "GUIDs," are a type of 128-bit number that can be used to generate unique values for primary keys in situations where auto-incremented values may be duplicates. Due to their guaranteed uniqueness, they are also helpful for generating random test data. They can be used as a source for creating random strings.

There are various tools available online for random uuid generator. Some of the most popularly used tools available online will be discussed in this article.

Versions of UUID

The UUID (Universally Unique Identifier) is a widely used standard for generating unique identifiers. According to the official UUID specification (RFC 4122), there are five different versions of UUIDs, each with its own purpose and usage scenario. Additionally, there is an unofficial version. Each version is explained below:

UUID Version-1: This version is based on the current time and the MAC address of the computer or "node" generating the UUID. The timestamp is the number of nanoseconds since October 15, 1582 at midnight UTC. However, most computers do not have a clock that ticks fast enough to measure time in nanoseconds, so a random number is often used to fill in timestamp digits beyond the computer's measurement accuracy.

A random MAC address is utilized instead of the actual MAC address of the node in some implementations.

UUID Version-2: This version is based on the DCE Security version, with a version number of this UUID set to 2.

UUID Version-3: This version is generated by taking the MD5 hash of a namespace identifier and a name.

UUID Version-4: This version is generated using a random or pseudo-random number generator.

UUID Version-5: This version is generated by taking the SHA-1 hash of a namespace identifier and a name.

It is important to keep in mind that each version has its own purpose and usage scenario, and it's recommended to use the appropriate version for your specific needs.

How is the UUID useful?

UUID (Universally Unique Identifier) is a standard format for identifying unique objects or records in a computer system. They are often used to identify resources such as database records or files, and can also be used as tokens for authentication or as keys in distributed systems. UUIDs are typically 128-bit numbers, represented as a string of hexadecimal characters, and are generated using a combination of the current time, a system identifier, and a randomly generated number. They are designed to be unique across different systems and networks and have a very low probability of collision.

UUIDs vs. Simple Identifiers

UUIDs Simple identifiers
Unique across different systems and networks. Unique within a single system or database
Generated randomly, not based on central authority Assigned by a central authority, like auto-incrementing integers in a database table
Designed to be unique across different devices More efficient to use, take up less space, and can be compared more quickly
Useful for globally and independently identifying something Useful for identifying something within a single system or database

What is a Random UUID Generator?

A random UUID generator is a tool that generates unique identifiers using a random algorithm. These UUIDs are generated using a pseudorandom number generator (PRNG) to ensure that the probability of collision is extremely low. They are often used in computer systems, databases, and distributed systems where unique identification is required. 

The generated UUIDs are formatted as a string of hexadecimal characters in the standard format (xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx) specified in RFC 4122. They can be generated either offline or online and can be used for a variety of purposes, such as identifying resources, generating tokens for authentication, or as keys in distributed systems.

Let’s see some of the most popularly used random UUID generators.

1. LambdaTest’s Random UUID Generator

LambdaTest is a cloud-based cross browser testing platform that allows users to test their websites and mobile applications on different browsers, operating systems, and devices. With LambdaTest, you can automate web app testing using different testing frameworks like Selenium, Cypress, Playwright, and more.

The UUID tool by LambdaTest is a unique identifier generator tool that creates universally unique identifiers (UUIDs) for use in various applications and systems. It offers a UUID v4 generator(random UUID) which creates version-4 universally unique identifiers according to RFC 4122. A Universally Unique identifier (UUID) is a 128-bit sequence of hexadecimal characters that is used to ensure uniqueness.

The ID is composed of a combination of numbers and letters, specifically, the numbers 0-9 and the letters A-F. The hexadecimal digits are organized in groups of four, separated by hyphens, and presented in the format XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX. Each of the four hyphens represents 8 bits (or one hexadecimal character). The last segment of the UUID, known as the "N position," indicates additional information such as format and encoding in a single to three bits.

A typical example of a UUID is 805a4340-d5e0-4587-8f04-0ae88219699f. It doesn't matter whether the letters A-F are in upper or lower case. According to RFC 4122, version-4 UUIDs are generated in such a way that six bits at certain positions have specific values. 

2.  Random UUID Generator by ExtendsClass

This website provides an online tool to generate UUIDs. A new UUID is automatically generated when the page is accessed. Additionally, you can generate multiple UUIDs at once by using the bulk option, and you can also generate UUIDs through a REST API by using the API section. The website uses the npm module "UUID" to create these unique identifiers.

3. Random UUID Generator by Testsigma

A version 4 UUID, also known as a random UUID, is defined in RFC 4122 and is composed of 128 bits. These bits are randomly generated, with certain positions set to specific values. This type of UUID is commonly used as a unique identifier for various applications and is considered to be a secure method of generating unique identifiers as the likelihood of two randomly generated UUIDs being the same is extremely low. An online random UUID generator can be used to quickly and easily generate these unique identifiers for use in your applications or systems.

The random UUID() method generates a type-4, cryptographically strong, pseudo-random UUID. It is a universally unique identifier that is created by using a pseudo-random number generator. This type of UUID is suitable for use in various applications as it is highly unlikely that two randomly generated UUIDs will be the same.

4. Random UUID Generator by ONLINETOOLS

An online random UUID generator is a simple tool that allows you to generate a random universally unique identifier (UUID) with just a click of a button. These UUIDs are created based on the standard defined in RFC 4122 and are composed of randomly generated bits. The tool is usually easy to use, and there are no distractions such as ads, popups, or other unnecessary elements. The tool is designed by developers from Team Browserling.

5. Baeldung’s Random UUID Generator

Baeldung is a website that provides comprehensive and in-depth tutorials on various programming topics, including the Java programming language. They also provide an online random UUID generator as a tool for developers. The generator uses the Java programming language and the java.util.UUID class to generate random universally unique identifiers (UUIDs). The generator can be accessed online, and it allows developers to generate random UUIDs easily and quickly.

6.  Random UUID Generator by uuidgenerator.net

Java has advanced significantly since its humble origins at Sun Microsystems in 1991. It now dominates enterprise backend software, powers the majority of smart phones (Android), and is widely used on desktop PCs in programs like LibreOffice and Minecraft.

7. Random UUID Generator by Webtools

The Webtools Online UUID (GUID) Generator is a free tool available online that generates various versions of UUIDs for use in software components, database keys, or any other situation where unique identifiers are needed.

You can generate UUIDs that are time-based, name-based, random, or nil using the Webtools - Online UUID (GUID) generator, among other things. To generate a time-based UUID, you must select the "V1 (time-based) UUID" option from the "UUID Version" dropdown, select the desired quantity from the "UUID Quantity" dropdown, and select your preferred "UUID formatting" options. To generate a name-based UUID, you can select either the "V3 (name-based | MD5 hash) UUID" or "V5 (name-based | SHA1 hash) UUID" option from the "UUID Version" dropdown, select the desired quantity, and enter a name.

To generate a random UUID, you must select the "V4 (Random) UUID" option, select the desired quantity, and select your preferred formatting options. To generate a Nil UUID, you must select the "Nil UUID" option, select the desired quantity, and select your preferred formatting options. Finally, click the "Generate" button to generate the desired UUID.


Thus, we see that the random UUID generators are useful to developers in a variety of ways. Some of the important benefits can be summarized as follows:

Unique Identifiers: Random UUID generators can be used to create unique identifiers for resources such as database records, files, and network connections, ensuring that there are no duplicate values or conflicts.

Unpredictable: Because UUIDs are generated using a random number generation method, they are unpredictable and not easily guessable, which can increase security and prevent unauthorized access to resources.

Platform-independent: UUIDs are a standard method of generating unique identifiers, and can be used across different platforms and systems, making them useful for developers working on cross-platform projects.

Easy to implement: Many programming languages have built-in libraries and modules that make it easy to generate random UUIDs, so developers do not have to write their own code.

Scalability: The use of UUIDs can improve the scalability of the application, as they can generate unique identifiers that can be used to identify and track across multiple systems or services.

Distributed Systems: The use of UUIDs can be particularly useful in distributed systems, as they allow for the identification of resources across multiple servers or devices.

We can choose from the random online generator tools available online, including the ones discussed above.