The two versions Bluetooth have same functions at same frequency band(2.4GHz ISM). but different performance, first of all Bluetooth 4.0 was launched in 2012, while bluetooth5.0 was launched in 2016, let’s list their difference as below:
Transmission Speed
Bluetooth 5.0 could transmit data at 2Mbps speed, while V.4.0 could only transmit at 1Mbps speed.
Covering Range
Bluetooth 5.0 could cover 300M range, but V.4.0 could only cover 100M. The below Estimator is just for reference. Users could also see the path loss factors.
Power requirement
The Bluetooth 5.0 require much less power consumption, the Bluetooth5.0 device could work longer compared to Bluetooth 4.0 device. Of course, the connection complexity would also consume more power on the same version Bluetooth device.
Message capacity
The Bluetooth 4 has a small message capacity of about 31bytes which gives just 17 to 20 bytes for actual data payload while the Bluetooth 5 with a large capacity of 255bytes gives more bytes for actual data payload.
Bluetooth beacon
With Bluetooth 5.0 beacons have become more popular due to the speed and covering range increase while with Bluetooth 4.0, they are less popular due to the less speed and range as well as low message capacity of 31bytes.
Support IoT devices
Bluetooth 5.0 easily meets the requirements for IoT devices with its good range and increase in speed while Bluetooth 4.0 does not due to its low speed and short working range. That means IoT devices will work well with Bluetooth 5.0 devices and utilize all its features properly, like the helmet Bluetooth earphone.
Compatibility
Bluetooth 5.0 devices could work with all V1.0/2.0/3.0/4.0/4.1 devices, but V4.0 can’t work with higher version devices.
