Here’s Why You Shouldn’t Use Your Phone for Internet Speed Tests

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Most of us use our phones for practically everything, so it just seems natural to grab your phone to run a speed test on your home internet connection. Here’s why you should avoid doing that—and what to do instead.

Why Your Phone Shows Inaccurate Results

A question we often field from our concerned neighbors and friends is “I ran a speed test on my internet. Why is it way slower than what I’m paying for?”

That’s certainly a valid question. Who wants to pay for the top-tier internet package only to get the budget-tier speeds? Usually, when we dig a little deeper, we find out the person ran a speed test on their smartphone and they’re upset the result is a fraction of the anticipated speed. But that outcome is to be expected in most cases.

How Speed Tests Work

To understand why people often get slow speed test results when testing from a smartphone, we have to look at how speed tests work.

We’ve looked at how internet speed tests work in detail, but here’s one relevant point to keep in mind: The key detail is this: any time you conduct a speed test, you are not connecting your general internet connection to the speed test server. You are connecting the device you’re running the speed test on to the speed test server.

Your Phone’s Wi-Fi Connection Is a Bottleneck

The device, in this case your phone, has to navigate through your home network first and every single thing between that device and the speed test server is a potential bottleneck. The second your maximum bandwidth exceeds the capacity of any piece of network hardware between your modem and the testing device, you’re going to get inaccurate results.

If you’re getting speed test results that are a fraction of the internet speed you pay for while using your phone, the likely culprit behind the bottleneck is your Wi-Fi router and/or the Wi-Fi device you’re running the test on.

Why? Because, except for folks with slower connections, the overall speed of the internet connection (as measured directly at the modem) is faster than what a single connection between the Wi-Fi hardware and any Wi-Fi device can handle.

This includes not only smartphones but everything else on the network using Wi-Fi including tablets, laptops, game consoles, streaming devices, and smart TVs. If your overall broadband speed is higher than what the Wi-Fi gear in your house can handle, you’ll always get inaccurate results running a speed test using a Wi-Fi device.

The exception to this rule, of course, is if you’re rocking really nice hardware connected to a slow broadband connection. A new Wi-Fi router paired with a new smartphone has more than enough bandwidth capacity to outpace a 25 Mpbs DSL connection.

Comparing Wi-Fi and Ethernet Speed Tests

What does this look like under real-world conditions? Let’s jump right into an example that will likely feel familiar to tons of folks who have run speed tests using their smartphones and unknowingly run into the bottleneck problem.

Say you have a gigabit fiber or cable internet connection. Here’s what a speed test conducted with your phone might look might look like.

Jason Fitzpatrick/Speedtest.net

Our first sample test was run using the Speedtest.net iOS app on an iPhone 13 connected to a Wi-Fi 5 network on a gigabit fiber connection in a residential location.

Approximately 240 Mpbs to a single device is certainly not a terrible connection speed, to be sure. At that speed, there’s no amount of streaming video or mobile game updating you’ll be doing that leaves you saying “Ugh, why is this stupid phone so slow?” But it’s clearly not the speed you’d expect from a gigabit fiber connection. So, if you ran this test right after you got gigabit fiber installed, you’d probably be a bit dismayed.

We conducted the same test, using the same iPhone 13, but connected to a Wi-Fi 6 access point on the same home internet connection.

Switching from a Wi-Fi 5 access point to a Wi-Fi 6 access point yields a significant increase in both upload and download speed because the iPhone 13 can take advantage of the improvements Wi-Fi 6 offers. But it still doesn’t accurately reflect the bandwidth of the internet connection. You’d be happier with this test, but would likely still wonder why you’re paying for gigabit internet if you’re not getting it.

Here’s the same test, conducted with a desktop computer with Gigabit Ethernet using the Speedtest.net site, all while connected to the same home network and internet connection.

An example of a speed test conducted using a wired Ethernet connection and a desktop computer.
Jason Fitzpatrick/Speedtest.net

The speed test results here, approximately 945 Mbps, are more reflective of the kind of speed you would expect from a gigabit fiber connection. Considering we didn’t kick everyone off the LAN to conduct this test or run it in total isolation, we’re not worried about it not being a perfect 1000/1000. Accounting for general overhead and activity, that’s accurate enough.

If we had tested the same connection using a laptop’s Wi-Fi connection and then plugged the laptop into the router via Ethernet to test again, you could expect to see the same results despite the test being conducted on the same device. Ethernet will consistently outpace Wi-Fi in any sort of sustained speed test.

How Should I Test My Internet Speed?

If testing your internet speed using your phone is out of the question (in cases where your internet speed is higher than what your phone and Wi-Fi router can handle,) then what should you do?

Test at the Router Level

Remember just a moment ago when we emphasized that a speed test is actually testing the connection between the test device and the speed test server? Ideally, you should test your internet speed with a device that is connected as closely and efficiently to the modem as possible.

If you have a modern router with beefy internal hardware, there’s a good chance that you can conduct a speed test on the router itself by logging into the router’s control panel and starting the test there. In terms of proximity and efficiency, it’s pretty tough to beat running the test right on the hardware that pipes the internet connection into the rest of your network.

Test Using an Ethernet Connection

Another good solution, if you can’t run the test on your router, is to use a device with an Ethernet interface such as a laptop, desktop PC, or even a game console. Plug the device directly into your modem and conduct the test that way. If you already have a setup in place with a network switch connected to your modem/router, you can always plug into that instead.

Assuming you’re not using a dusty old 10/100MB switch with your new fiber modem or running the test with a really old laptop with a 10/100MB port, this is just as good as running the test on the router itself as long as your hardware is up to snuff.

Can’t Do Either? Contact Your ISP

If you don’t have a router that supports on-device testing and your household is completely Wi-Fi without any ethernet devices to test the router with, you’ll either need to borrow some equipment from a friend or contact your ISP.

You’ll also want to contact your ISP if you run the speed test with proper hardware and the results aren’t what you expect, so they can help you rule out any issues. It’s possible something isn’t configured correctly on their end.

In both situations—lack of testing hardware or results that show there’s a problem—they can always send out a technician to your home to hook a diagnostic tool right up to the line and rule out any connection or hardware issues on their side of the equation.

Should it turn out the problem is in fact your network gear because your Wi-Fi router is old enough to start driver’s training, it’s probably time to upgrade to a new one.