What is WiFi signal strength?

WiFi signal strength refers to how strong the radio signal is between your home router and your device. The stronger the signal, the better your router can deliver the speeds you need.

Understanding WiFi signal strength

WiFi signal strength is closely connected to speed, but it’s not quite the same thing. Speed is how fast the internet is delivered into your home. Signal strength, on the other hand, determines how fast your router can deliver a connection to your devices. For example, you could have an ultrafast Gigabit fibre broadband package that delivers speeds of up to 1130Mbps. However, if the signal strength between your router and devices is poor, you won’t be able to make full use of these speeds.

What is a good WiFi signal strength?

When it comes to WiFi signal strength, ‘good’ is subjective. What counts as ‘good’ really depends on what sort of online activities you want to carry out. What sort of internet users are in your household?

  • Lower-need users are those who use the internet only for light activities that don’t demand much speed or bandwidth. Typical activities include browsing standard web pages and sending emails.

  • Average-need users are those who demand a little more of their day-to-day internet service. Typical activities may include using VoIP, using smart speakers, or watching YouTube videos.

  • Higher-need users are those carrying out more demanding activities, such as streaming 4K TV shows and movies, downloading large files and documents, video conferencing, and gaming.

The type of user you are, will determine what a good signal strength is for you. Generally speaking, -67 dBm is the minimum signal strength for any online activity. Signal tends to be very unreliable beyond this, and at -90 dBm you’re unlikely to be able to connect at all. You should be aiming for 60 dBm if you’re an average user, and 50 dBm or better for carrying out high-bandwidth activities.


Why does WiFi signal strength matter?

WiFi strength matters because, unless you’re using a wired network, it’s what’s going to determine how much of your provider’s advertised speed you’re able to utilise. At a time when people are doing more and more online and from home, having a fast and reliable broadband connection is essential.

Today, you may be using your home internet connection to log into the cloud and access your business’s files. Tomorrow, you may need to hold a video conference with international clients. In the evening, you might want to relax by streaming the latest blockbuster. And at the weekend, maybe you’ll send an email to friends and family, do some online banking, research your next holiday, and more.

Poor WiFi signal can make carrying out these activities frustratingly slow. Your signal might keep dropping, interrupting what you were doing. Or in the worst-case scenario, you may not even be able to secure a connection between your device and router at all.

Good WiFi signal strength is key to ensuring you can easily do everything you need, whenever you need.

How is WiFi signal strength measured?

There are a few different ways that WiFi signal strength can be measured, including in milliwatts (mW) and RSSI (Received Signal Strength Indicator). However, the most consistent and readable measurement is decibels relevant to a milliwatt (dBm). This has become the industry standard.

dBm is measured on a negative scale, usually running from 0 to -100, with 0 dBm indicating the best possible signal strength. The lower the number on the scale, the worse the WiFi signal strength.


What’s your WiFi signal strength?

Do you know what sort of WiFi signal strength you have at home? If not, don’t worry. There are a few different ways to find out.

The easiest way is to check the WiFi indicator on your chosen device. Every connected device – laptops, smartphones, tablets, and so on – will show an indicator at the top or bottom of the screen. This looks like a small dot with curved lines of different lengths above it. The more lines that are highlighted – there are usually four or five – the better the strength. This is a very easy way to determine connection.

If you own a Mac, there’s a great way to gain even more information and see your actual dBm measurement. Just hold down the option key [⌥] and click your mouse on the WiFi symbol in the top menu. You’ll be able to access your dBm measurement in the RSS field. Unfortunately, there isn’t an equivalent for PC, so it’s best to stick to the simple WiFi indicator method mentioned above.

If you want to test the strength of your WiFi signal on a mobile device, you’ll be able to download a WiFi speed checker from your phone’s app store. These are very quick and easy to get started with. It’s important to remember, however, that WiFi signal strength will vary in different parts of your home. And even across your different devices.

For example, you might have excellent signal on your laptop in the living room, but that doesn’t necessarily mean you’ll have the same great signal when using your laptop in the bedroom. And you might have strong signal in the kitchen on your phone, but trying to use your tablet in the same location could be a bit of a nightmare. That’s because there are lots of different elements that can impact the strength of your WiFi signal. It’s not a constant.

What impacts WiFi strength?

WiFi signal strength can change for many different reasons. Here are some of the most common:

  • Distance: WiFi signal strength can be affected by how far away your device is from the router. A device should be within one metre of the router to receive the best possible signal[1]. At three metres away, strength begins to drop, and it continues to drop the further away you go.

  • Obstacles: The WiFi radio signal cannot travel well through obstacles such as walls, doors, windows, and furniture. So if your router is in the living room but you’re trying to access the web from the kitchen, the signal will weaken with every obstacle it has to travel through.

  • Interference: WiFi signal can interfere with other radio signals on the same frequency. This means that your strength may be affected by things such as your neighbour’s WiFi signal, baby monitors, microwaves, decked phones, and more. The more interference, the weaker the signal in most cases.

  • Device: Sometimes, it’s not the strength of the signal itself that’s the problem but the status of the device that’s receiving that signal. Older devices especially can sometimes be problematic. As new WiFi technologies are rolled out, older devices may struggle to handle them in the best possible way.

[1] Ofcom, ‘Wi-Fi performance testing of broadband routers.’ May 2020. Available here.

Can WiFi signal strength impact speed?

One of the most important things to understand is whether your speed frustrations are coming from a poor connection, or whether there’s something else lurking in the background. It’s sometimes easy to think that slow speeds are due to the WiFi signal strength between your device and your router. In some cases, however, the actual signal may be very good but the speed of your broadband is still too slow.

Your WiFi signal is only able to deliver the best speed available with your current setup. It can’t magic faster speeds out of thin air. If your signal strength is good and you’ve tried all the tricks to improve it, but you’re still not seeing much increase in terms of speed, take a look at what speeds you’re getting from your provider.

If you need faster speeds, Virgin Media offers some of the fastest broadband speeds out there. Use the Virgin Media postcode checker to see what broadband services are available in your area.

Date Published: 10th November 2022
Article Updated: 25th January 2023

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