. Speed Test CenturyLink

Troubleshoot email, wireless, intermittent connection and slow speeds Setup and Troubleshoot e-mail software Security Downloads, Information, and Terms Setup and Troubleshoot Modems Setup and Troubleshoot Wireless on your Computer or Modem step-by-step tutorials on wired troubleshooting, wireless troubleshooting and email

Welcome to the Speed Test

A slow internet connection can be very frustrating. This section will give you the tools needed to improve your experience.

1. To get the most accurate test results:

*This app will give you an idea of what your speeds are. The app will not reflect your true speeds because the server is not hosted on the CenturyLink Network and because of factors that can affect your Wi-Fi connection.

2. Run the 'Speed Test'

If you have a Flash version released prior to, you may get a Latency Test Error after running the speed test. If you get a Latency Test Error:

3. Compare Speeds

Compare your results to the table below. The 'target speed' is 80% of your 'download/upload speed'. This is because 20% of the speed is used for protocol overhead. Testing should be done with 1 device connected directly to your modem using an Ethernet connection. All other devices should be disconnected and powered off during testing. Want to learn more, check out other factors that can slow down your Internet.

Download* Overhead Target^
1.5 Mbps -20% 1.2 Mbps
3 Mbps -20% 2.4 Mbps
4 Mbps -20% 3.2 Mbps
5 Mbps -20% 4 Mbps
6 Mbps -20% 4.8 Mbps
7 Mbps -20% 5.6 Mbps
10 Mbps -20% 8 Mbps
12 Mbps -20% 9.6 Mbps
20 Mbps -20% 16 Mbps
40 Mbps -20% 32 Mbps
1 Gig -20% 800 Mbps
Upload* Overhead Target^
896 kbps-20% 716 kbps
3 Mbps -20% 2.4 Mbps
5 Mbps -20% 4 Mbps
20 Mbps -20% 16 Mbps
* Not all speeds are available in all areas.

^ Tests run over a Wi-Fi connection may not represent your full broadband connection speeds. Learn about factors that can affect your Wi-Fi connection speeds.

4. My Speeds are:

Everything tests good!

Keep in mind, the more devices you connect, the less speed you have available.

You can check for faster speeds in your area.
Don't worry, we can show you some tricks:

1. First, read the article "improving speeds". After you're done...

2. Run another speed test.

3. Still having issues? Contact Support.
Wired connections are faster and should be used whenever possible.

With that in mind, here are some tricks to improve Wi-Fi.

Windows 10

If you have Windows 10 connected to your network, it could be slowing you down.

Windows 10 has a feature known as Windows Update Delivery Optimization (WUDO). This feature was designed to help users get their software updates quicker, by using peer-to-peer sharing. This setting, when enabled, uses your Windows 10 computer to provide other Windows 10 users a portion of their download (like a bittorrent service).

The result, your Internet slows down while updates are being "shared" across the internet to other Windows 10 users.

How do you turn off Windows Update Delivery Optimization (WUDO)?
  • Go to "Start"
  • Select "Settings"
  • Select "Update & security"
  • Select "Windows Update"
  • Select "Advanced options"
  • Select "Choose how updates are delivered"
  • Under the section "Updates from more than one place", turn the toggle to the "Off" position.

More information about this issue can be found at Microsoft.com: Windows Update Delivery Optimization: FAQ. If you can't connect to the Internet on a Windows 10 computer, click here. (WINSOCK ISSUE)

Wireless Connections

Speed tests performed over a wireless connection don't reflect your full connection speed. Keep in mind that wired connections are faster, more secure, more dependable and should be used whenever possible.

With that in mind, we can show you some tricks to improve your wireless connection.