How Can I Tell If My Broadband Speed Is Correct?
On this page
Understanding broadband speed: Mbps and MB/s explained
What speed do I actually need?
How does broadband get to my home and why does it matter?
What’s my minimum guaranteed speed and what are my rights if I don’t get it?
How do I test my broadband speed?
Why do speeds vary by time of day?
Introduction
Broadband is now as essential as electricity, gas and water. But unlike those other utilities, most of us have no way of knowing whether we're actually getting what we pay for.
Millions of customers are paying for speeds they'll never actually get. And most don't know they have the right to walk away from their contract without paying a penny in penalties.
Here's what you need to know, and how to make sure you're not being shortchanged.
At BroadbandUK, we want to help people understand their broadband service. Here's our guide to the most common questions we're asked, plus a few tips to get the most from your connection.
Understanding broadband speed: Mbps and MB/s explained
Broadband speed is measured in megabits per second (Mbps). The more megabits per second, the faster your downloading, streaming and uploading will be.
You may notice something confusing: your broadband package promises "50 Mbps" but your downloads show only "6 MB/s". This is not a problem. Broadband is advertised in megabits per second (Mbps), but your computer displays download speed in megabytes per second (MB/s). One megabyte equals eight megabits, so a 50 Mbps connection delivers around 6 MB/s. That is fast enough to stream films or download a music album in seconds.
But what if your package promises "up to 100 Mbps" and your speed tests show only 35 to 60 Mbps? Providers advertise the best possible speed, but factors like copper wiring, distance from your street cabinet and network congestion at peak times can all reduce what you actually get.
That is why your guaranteed minimum speed matters more than the advertised maximum. You will find it in your contract or key facts sheet. The maximum shows what is possible in perfect conditions. The guaranteed minimum is what your provider is legally obliged to deliver.
What speed do I actually need?
As a general rule, around 10 Mbps is enough for browsing and sending emails. 25 Mbps should cover HD streaming for one or two users. Families, gamers or anyone watching 4K video may need 50 Mbps or more. If you have got four people in your family, each with a smartphone, TV streaming, a couple of laptops and a gaming system, you could need significantly more than that.
How does broadband get to my home and why does it matter?
Broadband can arrive through different types of connection: full fibre, part-fibre with copper, cable or even 4G/5G mobile. Full fibre is the fastest and most reliable. Part-fibre with copper slows down the further it travels from the local exchange. This might seem bonkers, but it’s true - homes miles away from the exchange get much slower speeds than those nearby. Cable connections can offer very high speeds where available, though full fibre remains the gold standard. Mobile connections can be quick but are less consistent. Knowing which type of broadband connection you have should give you an indication of what speed you can expect.
What’s my minimum guaranteed speed and what are my rights if I don’t get it?
When you sign up for a contract, providers are quick to advertise the fastest speed you might get. But the figure that really matters is your guaranteed minimum, which you will find in your contract or key facts sheet. If your speed keeps falling below that minimum and your provider cannot fix it, you have the right to leave your contract without penalty.
How do I test my broadband speed?
There are plenty of free broadband speed tests available. BroadbandUK offers one at broadbandspeedtest.org.uk, along with Ofcom-recommended sites.
The best way to test is to connect your computer directly to your router with an ethernet cable rather than Wi-Fi, turn off other devices, and run tests at different times of day. Repeat this over a few days to build up a reliable picture.
If you are looking for a new supplier, bear in mind that comparison sites show advertised speeds based on what at least 50% of that provider's customers on the same package actually receive at peak times (8pm to 10pm). That does not mean it is the speed you will get at your address.
Why do speeds vary by time of day?
Many homes share local broadband networks, which means speeds can dip in the evenings when more people are online. If you are seeing major slowdowns or ongoing issues, do not just put up with it. Report the problem to your provider as it could point to a wider network issue they need to fix.
What quick fixes at home can boost my speeds?
Place your router in an open area, away from walls, metal objects, and appliances like microwaves that can interfere with the signal. For the fastest connection, use a cable to connect devices like your TV, games console, or computer directly to the router. Limit the number of devices online at once. If you have a larger home, Wi-Fi extenders or mesh systems can help reach dead spots.
Do upload speed and ‘latency’ matter for me?
Upload speed affects video calls, cloud backups and sharing large files.
Latency refers to the delay between your internet connection receiving an instruction and acting on it, often shown as 'ping' in speed tests and measured in milliseconds (ms). When gaming, you may notice a lag between pressing a button and seeing the action happen. On video calls, there can be a delay between when you speak and when others hear you. That is latency. Low latency makes gaming smoother and video calls clearer.
Meet the author:
Martyn James
Consumer Expert, Journalist & Broadcaster
Martyn James is an award-winning consumer rights expert and journalist with over 20 years’ experience covering issues such as consumer services, household bills and broadband availability in the UK. He is the resident consumer expert on BBC One’s Rip-Off Britain and regularly appears on BBC Morning Live, The One Show and Watchdog. Martyn also writes weekly consumer advice columns for The Times and Sunday Times, Daily Mirror.