Bluetooth 5 FAQ: Everything you need to know

Bluetooth is everywhere, and it’s only growing more commonplace. What started as a way to connect dorky-looking headsets has grown into a robust wireless protocol that links everything from headphones to heart monitors, wearables to weather stations.

The latest Bluetooth revision, Bluetooth 5, makes significant improvements, especially to the low energy operation modes. It’s aimed at preparing the technology for the coming flood of Internet of Things (IoT) devices, and if you have an iPhone 8 or X, it’s already in your phone. Here are five things you need to know about the latest version of this ubiquitous wireless technology.

It’s just ‘Bluetooth 5’

Previous versions of Bluetooth, all the way back to 1.0, had a decimal point. You would see “Bluetooth 3.0” or “Bluetooth v4.1” listed on spec sheets. Most recently, in the 4.0 update, Bluetooth added a new low-energy protocol often listed as “Bluetooth LE.”

With this new version of Bluetooth, the special interest group (SIG) that controls the spec has opted to simply call it “Bluetooth 5” with no decimal point, no “v,” and no “LE.” Yes, it still included the low energy protocol (and it has been greatly improved), but it’s all wrapped up into one simple brand: Bluetooth 5. The Bluetooth SIG wanted to make the branding simpler and easier for the public to understand.

You’ll need new hardware

In order to take advantage of Bluetooth 5, you’ll need new Bluetooth 5 gear. If you have an iPhone 8/Plus, or iPhone X, you’ve already got the phone part taken care of. Apple was one of the first to ship a Bluetooth 5 compatible phone (along with Samsung in the Galaxy S8). 

But the devices you connect to have to use Bluetooth 5 compatible hardware as well. That means Bluetooth 5 headphones, smart home devices, speakers, mice, keyboards…whatever. Bluetooth 5 is quickly becoming the norm on high-end phones, but those other devices, not so much. We probably won’t see a proliferation of Bluetooth 5 compatible peripherals until phones, tablets, and laptops that support the new spec are more commonplace.

It’s backwards compatible

The good news is, Bluetooth 5 hardware is fully backward compatible with prior versions of Bluetooth. Your Bluetooth 5 phone will have no problem at all working with all the Bluetooth headphones, speakers, fitness trackers, automobiles, and everything else out there. You won’t get any of the benefits of the new technology, though—it will work as if you didn’t have Bluetooth 5 capability in your phone, tablet, or computer at all.

The maximum range is longer

The Bluetooth 5 spec allows low-energy transmissions to sacrifice data rate for more range. A lot more range: up to four times the range of Bluetooth 4.2 LE, for a maximum of around 800 feet. That’s a theoretical maximum, mind you. In the real world, you can expect much less, though it’s still going to be a huge improvement over older versions of Bluetooth.

You won’t get that kind of range all the time on all devices, mind you. Developers have to consciously choose to sacrifice total bandwidth for range. But it’s perfect for many Internet of Things (IoT) devices, which often transmit small amounts of data but need to reach all over a house or a large store.

The maximum bandwidth is a lot higher

In addition to the capability to sacrifice bandwidth for greatly extended range, Bluetooth 5 adds a new interface to double bandwidth at the expense of power. This new physical layer (PHY) supports speeds of up to 2 megabits per second and higher transmission power of +20dB in low energy mode.

In other words, the new Bluetooth version offers two interfaces for low energy operation: one to transmit less data over much longer distances, and one to transmit twice the data over a shorter range.

This is great news for devices that need to transmit bursts of large amounts of data (like a firmware update) or for data-hungry applications like audio or video. It also means that we may one day see Bluetooth headphones that use the low-energy spec, which could massively increase battery life. Sadly, Bluetooth 5 does not include a standard audio transmission protocol within the low energy spec, so for the time being, bluetooth headphones and headsets will continue to use the more battery-draining Bluetooth Classic modes.

It’s aimed at the Internet of Things

Nearly all of the big improvements in Bluetooth 5 are exclusively for its Low Energy mode (BLE). First introduced in Bluetooth 4.0 and then improved in the v4.1 and v4.2 releases, BLE is a whole separate protocol from “classic” Bluetooth. As of Bluetooth 4.2, the BLE mode transmits a lot less data than classic Bluetooth, but it has similar range, much lower latency, and uses just a fraction of the power. That’s why it is used so often in Internet of Things devices, beacons, tiles, fitness trackers, and anywhere where really long battery or low-power operation is key. 

Bluetooth 5 adds enhancements to low energy operation in addition to the optional higher-bandwidth or longer-range connections. For example, it brings an eightfold increase in broadcast data efficiency. That means, essentially, eight times as many connected devices.

The Bluetooth SIG imagined homes and businesses full of IoT devices, and engineered the Bluetooth 5 spec to make them more powerful, useful, and easier to connect to.