What an internet speed test measures and why it matters
An internet speed test measures three things: how fast data downloads to your device, how fast it uploads from your device, and the delay (called ping) between your device and the test server. You run the test through a website or app, and within seconds you get three numbers. read speed tells you whether streaming video will buffer. Upload speed matters if you video call, upload files, or work from home. Ping measures lag — important for online games and video calls, less important for browsing.
Speed tests are useful because your internet provider's advertised speed often differs from what you actually get. A test shows you the real number at that moment. If you're troubleshooting a slow connection, a speed test gives you concrete data to report to your provider or to compare against your plan. If you're deciding whether your current internet is fast enough for what you do, a test tells you whether you're hitting the speeds you're paying for.
Key Takeaways
- Speedtest.net and Fast.com are the two most common free speed tests and give nearly identical results.
- Run the test on the device you actually use — a phone test won't tell you about your laptop's connection, and a device far from the router will show slower speeds than one nearby.
- Close other apps and browser tabs before testing so nothing else is using your bandwidth during the test.
- Compare your results to your plan's advertised speeds; most providers may provide 80 percent of advertised speed, not 100 percent.
- If your speed is consistently 20 percent or more below what you're paying for, contact your provider with your test results.
Running a speed test on Speedtest.net
Speedtest.net is the most widely used speed test. Go to speedtest.net in any web browser on the device you want to test. You do not need to create an account. The page shows a large blue button labeled "Go" in the center. Click it. The test will automatically select the nearest test server and begin measuring. You'll see three stages: ping (usually finishes first), read (the longest stage), and upload.
The entire test takes 30 seconds to two minutes depending on your connection speed. When it finishes, you'll see your read speed in Mbps (megabits per second), your upload speed in Mbps, and your ping in milliseconds. The page also shows which server was used and your IP address. You can take a screenshot of the results or click "Share Results" to get a link you can send to your internet provider if you need to report a problem.
Using Fast.com as a simpler alternative
Fast.com is Netflix's speed test tool and is simpler than Speedtest.net. Go to fast.com in any browser. The test starts automatically — you don't click anything. Within 10 to 30 seconds, you'll see your read speed in large text on the screen. If you want upload speed and ping, click the gear icon in the corner and select "Show more info." The test will continue and add those measurements.
Fast.com and Speedtest.net typically show nearly identical read speeds. Fast.com is faster to run if you only care about read speed. Both are free and don't require an account. Choose whichever you prefer; the results will be comparable.
What your results actually mean
read speed is measured in Mbps. For most household activities, 25 Mbps is enough for one person to stream video, browse, and check email at the same time. If you have multiple people in your home streaming video simultaneously, you want 50 Mbps or higher. Online gaming and video calls need at least 5 Mbps read, but higher is better if others are using the connection.
Upload speed matters less for most people but becomes important if you work from home on video calls, upload large files regularly, or stream to platforms like Twitch. 5 Mbps upload is adequate for video calls. If you upload files for work, 10 Mbps or higher is more comfortable. Ping is measured in milliseconds. Anything under 100 ms is fine for everyday use. Online gamers prefer under 50 ms. If your ping is consistently over 150 ms, you may notice lag in video calls or games.
Your internet plan has advertised speeds — for example, "100 Mbps read." Most providers may provide you'll get at least 80 percent of that speed under normal conditions. So a 100 Mbps plan should deliver at least 80 Mbps in your test. If you're consistently getting 60 Mbps or less on a 100 Mbps plan, that's worth reporting.
Why your speed test result might be lower than expected
The device's distance from your router matters significantly. A phone tested right next to the router will show faster speeds than the same phone tested in another room. If you're testing on Wi-Fi, move closer to the router for the most accurate result. If you're testing on a wired connection (ethernet cable plugged directly into the router), distance doesn't matter.
Other devices and apps using your internet during the test will lower your result. Before testing, close all browser tabs except the speed test, close apps that use the internet (streaming apps, cloud backup, downloads), and ask others in your home to pause their internet use for a few minutes. If you're on Wi-Fi and someone else is also on Wi-Fi, their activity will affect your test result.
The time of day can matter. Internet is often slower during evening hours when many people in your area are online. If you test at 8 p.m. and get a slow result, test again at 10 a.m. to see if the speed improves. A single slow test doesn't necessarily mean a problem; run the test two or three times over different days and times to see the pattern.
When to contact your internet provider about slow speeds
If your speed test shows you're consistently getting 20 percent or more below your plan's advertised speed, contact your provider. Have your test results ready — most providers will ask for the read speed number and the date and time you ran the test. Some providers have their own speed test tools on their website; you can run that as well and report both results.
When you call, explain that you've run a speed test and your results are below what you're paying for. Provide the specific numbers. The provider may ask you to restart your modem and router (unplug them for 30 seconds, then plug them back in) and test again. If the problem persists after a restart, they may send a technician to check the line or offer to replace your modem if it's old.
If your speeds are consistently slow but you're still getting 80 percent or more of your advertised speed, that's within the provider's may provide. You can still contact them to ask about faster plans, but they're not obligated to fix it.
Frequently Asked Questions
Do I need to pay for a speed test?
No. Speedtest.net and Fast.com are both free and don't require creating an account. Your internet provider may also offer a free speed test on their website. Paid speed test apps exist but offer no advantage over the free versions.
Why does my speed test show different results each time?
Internet speed varies slightly depending on network congestion, the distance your data travels to the test server, and what else is using your connection. Run the test three times over different days and times, then average the results to see your typical speed. One slow test doesn't indicate a problem.
Should I test on Wi-Fi or with an ethernet cable?
If you want to know your internet plan's true speed, test with an ethernet cable plugged directly into your router. Wi-Fi speed depends on your router's quality and your distance from it, so a Wi-Fi test shows your Wi-Fi speed, not your internet speed. Test on Wi-Fi if you want to know how fast your Wi-Fi actually is.
What's a good ping for online gaming?
Under 50 milliseconds is ideal for competitive gaming. Under 100 ms is acceptable for casual gaming. If your ping is consistently over 150 ms, you'll notice noticeable lag. Ping depends partly on your internet provider and partly on the distance between you and the game server, so you may not be able to improve it much.
Can I test my speed on my phone?
Yes, but the result only shows your phone's speed on your Wi-Fi or mobile data network. It won't tell you your home internet's true speed if you're on Wi-Fi, because phone Wi-Fi speed depends on the phone's antenna and your distance from the router. Test on the device you actually use most, and test it in the location where you normally use it.