A speed test takes less than a minute, but a careless one can tell you very little. Run it on a phone at the far end of the house while someone streams a film downstairs, and the number on screen says more about your Wi-Fi and your family than about your broadband line. Done properly, a test shows whether you are getting what you pay for, and gives you evidence if you aren’t.
What a speed test measures
| Result | What it tells you | Why it matters |
|---|---|---|
| Download speed | How fast data reaches you, in megabits per second (Mb) | Streaming, browsing and downloads |
| Upload speed | How fast data leaves your home | Video calls, cloud backups and sending large files |
| Ping (latency) | How long a small piece of data takes to reach a server and return, in milliseconds | Online gaming and calls feel more responsive with a lower figure |
| Jitter | How much the ping varies from moment to moment | High jitter causes choppy calls and lag spikes |
Most free speed test websites and apps show all four. Your provider’s app usually has its own tester too, which often checks the speed reaching the router rather than your device.
How to run an accurate test
- Plug a laptop or computer into the router with an Ethernet cable. Wi-Fi adds too many variables for a fair reading of the line.
- Ask everyone else to pause streaming, gaming and downloads, and check that no device is backing up photos or installing updates.
- Close other apps and browser tabs on the testing device, and switch off any VPN.
- Run the test three times in a row and note the middle result.
- Repeat at different times over several days, including at least one weekday between 8pm and 10pm, when networks are busiest.
- Write down the date, time and results each time, or take screenshots. A record like this is what your provider will ask for if you report a problem.
Then run one more test over Wi-Fi in the room where things feel slow. Comparing it with the wired result shows whether the line or the Wi-Fi is the weak point.
Speed tests from broadband providers
Several providers run their own speed tests, and you don’t have to be a customer to use most of them. They work like any other tester, but a provider’s own tool can give its customers extra detail, such as the speed reaching the router as well as the device.
| Provider | What you get |
|---|---|
| Virgin Media | Download, upload, latency and jitter for anyone. Virgin Media customers also see packet loss and the speed to their hub |
| Vodafone | Download, upload, ping and jitter, using the Ookla testing service |
| TalkTalk | Download, upload, ping and jitter, using the Ookla testing service |
| Sky | Download, upload, latency and jitter. Sky Hub users see the speed to the hub too |
| BT | A quick download test, with tips on improving your speed |
EE customers test their speed in the EE app rather than online. Community Fibre suggests using an independent speed test app.
Why your result may be lower than your package
Your test can fall short of the speed on your bill for reasons that have nothing to do with the line:
- Wi-Fi. Walls, distance and interference all take their toll, and the loss grows with faster packages. Our guide to Wi-Fi boosters, extenders and mesh covers the fixes.
- The device. Older laptops often have Ethernet ports limited to 100Mb, and older phones and laptops with Wi-Fi 5 or earlier can’t reach the top speeds of a gigabit package.
- The time of day. Evening demand can slow part fibre and busy networks in particular.
- The test server. A distant or overloaded server gives a lower reading. Most tests choose a nearby server automatically.
- What the advertised figure means. The speed in an advert is the one at least half of a provider’s customers reach at peak time, so a good share of homes will always see less than it.
Reading your results
Compare your wired results with two figures from your provider: the average speed for your package, and the minimum guaranteed download speed you were given when you ordered. You’ll usually find both in your contract summary, welcome email or account.
| Your wired result | What it suggests |
|---|---|
| Close to the package average | Your line is fine. Any slowness is likely to be Wi-Fi or devices |
| Below the average but above your guaranteed minimum | Normal variation, especially at peak times, but worth monitoring |
| Below your guaranteed minimum on several tests | A possible fault. Report it to your provider |
| Very low or dropping out completely | Check for an outage, then report a fault |
To work out whether your package is fast enough for your household in the first place, see our guide to what broadband speed you need.
Fixing slow broadband
Work through these before calling your provider, as they solve a large share of problems:
- Restart the router by switching it off for 30 seconds. Leave it on afterwards, as frequent restarts can make some connections less reliable.
- Check your provider’s app or service status page for a fault in your area.
- Make sure the router is plugged into the main phone socket or fibre box, not an extension lead or a long phone cable.
- Replace old or damaged cables between the wall and the router.
- Move the router somewhere open and central, as our Wi-Fi guide explains.
- Look for devices using bandwidth in the background, such as cloud backups, game updates or a security camera uploading footage.
- Check your router’s software is up to date. Most update themselves, but an old router may need replacing. See our pages on the BT Smart Hub 3, Virgin Media Hubs, Vodafone routers and Sky routers.
Reporting a fault and your rights
If wired tests stay low after these checks, contact your provider and share your results. Many large providers have signed up to Ofcom’s broadband speeds codes of practice. Under the codes, you receive a minimum guaranteed download speed when you order. If your speed falls below it and the provider can’t put it right within 30 days of your report, you can leave without paying an exit fee. Since December 2022, that right also covers TV and landline services bundled with the broadband. Check your contract to see whether your provider has signed up.
If your connection stops working altogether and isn’t fixed within two full working days, providers in Ofcom’s automatic compensation scheme pay you for each extra day. Our switching guide lists the current amounts, and our guide to leaving a broadband contract early explains the other ways out of a contract.
When a faster connection is the answer
If your line is working properly but your speed still isn’t enough, the fix is a different connection rather than a repair. Part fibre can’t go beyond what the copper line allows, so check whether full fibre has reached your street using our broadband checker. Our best broadband picks compare the main options. If no fast fixed line is available, 5G and mobile broadband may outperform a slow copper connection.
FAQs
How do I check my broadband speed?
Connect a computer to your router with a cable, pause other internet use in the house, and run a speed test website or your provider’s app. Repeat it at different times, including in the evening, to get a fair picture.
Why is my speed test slower than my package?
Common causes are Wi-Fi, an older device, background downloads and busy evening periods. Advertised speeds are also averages that not every customer reaches. A wired test that stays well below your guaranteed minimum may point to a fault.
Should I test my broadband over Wi-Fi or a cable?
Use a cable to test the line itself. A Wi-Fi test is useful too, but only to measure how well your Wi-Fi performs in a particular room.
What is a good ping for broadband?
Under 20ms is excellent and typical of full fibre. Up to 50ms is fine for most uses, including casual gaming. Consistently higher figures can cause noticeable lag in fast online games and video calls.
Does a VPN slow down a speed test?
Usually, yes. A VPN routes your traffic through another server, which adds distance and can lower both speed and ping results. Switch it off when testing your line.
Can I leave my contract if my broadband is slow?
If your provider follows Ofcom’s speeds code and can’t restore your speed above the guaranteed minimum within 30 days of your report, you can leave without an exit fee.