A guide to broadband speed: What does it mean and what affects it?

From testing your speed to knowing the difference between Mb and MB - everything you need to know about broadband speed.

There may be occasions when you want to check your broadband speed, for instance to check whether your wi-fi is working as efficiently as it can right around your home.  

If you are a BT Broadband customer, checking your broadband speed is very easy.  On a PC, log into My BT, and on a smartphone, use the My BT app, which is available for Android and Apple devices.

As well as telling you your broadband speed, the My BT website and My BT app will let you know about any service issues in your area.

But once you’ve found out your broadband speed, what does it mean, and what can you do with this information? Check out the video above to find out more.

How is broadband speed measured?

Broadband speed is measured in megabits per second (Mpbs). This should not be confused with megabytes (MB) which refers to the size of a digital file such as an image, a song or a movie.

One megabit is made up of 1,000 kilobits, and broadband speed can refer to either download or upload speeds.

What’s the difference between download and upload speeds?

Download speed is important for streaming or downloading content for the internet, whereas upload speed is really important for sharing pictures or putting content on social media. The faster the speed, the quicker you will be able to download movies on BT TV, get music from Spotify, or upload photos and videos to social networks like Facebook and Instagram.

Different types of activity need different speeds, for instance streaming a Netflix TV show or movie in standard quality needs a recommended download of speed 3Mpbs, in high definition it needs to be 5Mpbs and in 4K/Ultra HD quality the recommended download speed us much higher at 25Mbps.*

BT offers plans with broadband speeds to suit all types of user, from an average speed of 10Mb up to an average speed of 67Mb with Superfast Fibre.

What factors affect broadband speed?

The speed of your broadband can be affected by several factors.

How close is your exchange? The closer you are to your telephone exchange, the faster your connection will be. Standard broadband uses copper cables to connect to the exchange, and the shorter the cable, the faster your broadband will be. With fibre optic broadband, copper is used to connect your house to the nearest cabinet, and again the shorter the distance, the speedier your broadband will be.

Is a website down? Sometimes, if a website is slow to load, it might have nothing to do with your broadband speed and everything to do with the performance of the site itself. If many thousands of people visit a site at once and the website can’t deal with such unexpected traffic, it can slow down and fail to load. There may also be occasions when technical issues take a website down. If this happens it’s worth checking the status of the site at https://downforeveryoneorjustme.com/ or try again later.

Location of your BT Hub: The position of your Hub can make a big difference to your wi-fi performance.  Put it in the centre of your house, so there are less thick walls to go through and the more rooms the signal will reach. On a table or shelf is ideal, so some of the signal doesn’t get sent through the floorboard.

Water absorbs the signal, so avoid putting it near a wish tank, next to your TV is a no-no as well – metal can reflect and scatter the signal. It may be tempting to hide your Hub in a cupboard – don’t, you’ll reduce the strength of the signal.

Finally… avoid putting it near a window or some of the signal will be sent outside and lost.

Who else is online? If multiple devices are using your broadband connection - for instance if you are streaming Netflix in the living room, while someone else ismar playing Xbox Live upstairs - the signal will be split and can seem slower. Make sure you disconnect any gadgets from the internet that don’t need to be online

Wired or wireless? There are two ways to connect your devices to your home broadband: via wi-fi or using an Ethernet cable which connects directly to your BT Hub. Wi-fi is the most convenient as you can connect devices wirelessly no matter where you are in your house. However, cabled Ethernet is faster and may be a better choice than wi-fi for data-intensive activity such as downloading a movie.

Wired broadband also has lower latency - the time it takes for data from your computer to travel to a server; in cases such as Xbox Live gaming, lower latency means you get a faster response when playing games online, which could be the difference between winning and losing.

Your equipment: Older gadgets can have slower wi-fi performance than newer gadgets. Our Smart Hub has the UK’s more powerful wi-fi signal, so if you’ve got an older router consider upgrading.

For more advice and tips check out our article: Slow broadband? Follow our simple tips to improve performance

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