Bluetooth wireless technology enables electronic devices to connect and communicate wirelessly. It is a standard for the short-range wireless interconnection of cellular phones, computers, and other electronic devices. Invented by Ericsson in 1994, it is a method of exchanging data over short distances using radio waves from fixed and mobile devices, creating personal area networks. Bluetooth technology operates by using the licence-free 2.4 GHz ISM band to transmit data, eliminating the need for wires or cables. It is designed for low power consumption, which makes it ideal for battery-operated devices. The technology is also designed to be simple and secure, with data encryption and user authentication measures in place. Bluetooth devices connect to each other through a process called pairing. Once a connection is made, data can be sent back and forth between devices. This is useful for a wide range of applications, including transferring files between devices, using a wireless mouse or keyboard with a computer, or using a hands-free headset with a mobile phone. Bluetooth technology continues to evolve, with new versions offering better speed, range, and functionality.

Bluetooth Versions

A Bluetooth version refers to the specific iteration or generation of Bluetooth technology. Each version represents advancements in range, speed, power consumption, and other features. The standardisation of these versions falls under the responsibility of the Bluetooth Special Interest Group (SIG), a not-for-profit organisation comprised of various companies in the areas of telecommunication, computing, networking, and consumer electronics.

Version Description

Bluetooth 4.0

Bluetooth 4.0 is a significant advancement in the Bluetooth technology standard. Introduced in 2010, this version is designed to be more energy-efficient and cost-effective, making it ideal for devices that run on coin cell batteries such as fitness trackers and other wearable devices. One of the ...

Bluetooth 4.1

Bluetooth 4.1, an upgraded version of the wireless communication standard, offers significant improvements over its predecessors. It provides a more robust, reliable connection and enables coexistence with 4G technology. This version introduces an automatic reconnection feature which allows ...

Bluetooth 4.2

Bluetooth 4.2 version is a power-efficient variant of the classic Bluetooth technology, which is designed for short-range communication between devices. This version was officially adopted in December 2014 and offers several significant improvements over its predecessors. One of the key features of ...

Bluetooth 5.0

Bluetooth 5.0 represents a significant advancement in the series of Bluetooth core specifications. Introduced in 2016, it provides four times the range, two times the speed, and eight times the broadcasting message capacity of Bluetooth 4.2, which was its predecessor. Key features of Bluetooth 5.0 ...

Bluetooth 5.1

Bluetooth 5.1, an updated version of the Bluetooth wireless communication standard, offers enhancements in performance and functionality. This version introduces a new feature called Direction Finding, which significantly improves location services. It allows devices to determine the direction of a ...

Bluetooth 5.2

Bluetooth 5.2 boasts enhanced performance, increased efficiency, and new features designed to facilitate more advanced use cases over its predecessors. One of the most notable enhancements is the addition of LE Audio. This feature allows for the transmission of audio over the Low Energy (LE) ...

Bluetooth 5.3

The Bluetooth Special Interest Group (SIG) rolled out the Bluetooth Core Specification Version 5.3 in July 2021. This new version brings a handful of feature enhancements, including: - Connection Subrating: This feature provides an improved method of managing the rate of data transmission between ...

Bluetooth 5.4

The Bluetooth SIG launched the Bluetooth Core Specification Version 5.4 in February 2023. This version introduces the following features: 

  • Periodic Advertising with Responses (PAwR) - PAwR is a novel Bluetooth Low Energy (LE) logical transport offering a method to execute energy-efficient, bi ...

Bluetooth Power Classes

Power Class refers to the different categories of Bluetooth devices, distinguished by their maximum power output. The power class of a Bluetooth device determines its range of communication, with higher power classes capable of longer range communication.

Version Description Output Power Max. Distance

Class 1

Bluetooth Class 1 represents the highest power level of Bluetooth devices, with a maximum power output of 100 mW (20 dBm). This class of Bluetooth devices has the longest operational range, typically up to 100 metres. However, this range can be theoretically extended up to 1 kilometre with a clear ...

20 dBm 100 m

Class 2

Bluetooth Class 2 devices, typically found in mobile devices and laptops, operate at a power level of 2.5 mW (4 dBm). The transmission range for these devices is approximately 10 metres. Class 2 Bluetooth devices are designed for short-range communication, making them ideal for personal area ...

4 dBm 10 m

Class 3

Bluetooth Class 3 represents the lowest power class among the three Bluetooth classes. With a maximum power output of just 1 mW (0 dBm), it has the shortest range, typically up to about 1 metre. It is primarily designed for short-range, personal area network devices, such as smartwatches, fitness ...

0 dBm 1 m