The ultimate speed test test

Everything you need to know about speed tests

Which speed test is best?

SpeedOf.me (speedof.me) is the most accurate speed test when using the max. download speed.

Internet Speed at a Glance (speedtest.zomdir.com) gives you the quickest insight.

If you are having trouble with the download speed provided by your ISP, you should use the speed test recommended by your ISP to identify these issues.

If you want to know if your download speed is enough for videostreaming, you should use Fast (fast.com).

The ultimate speed test test 2021The updated ultimate speed test test 2020Speed determining factorsThe three categories of speed testsISP Speed tests

Almost every speed test has a negative bias

Through trial and error I learned what the real internet speed is that my ISP delivers. That helped a lot to find out how good a speed test really is. During the process, I realized that there are actually three categories of speed tests. More importantly, even the 'Realistic' category speed tests have a negative bias.

Recently my ISP increased the download speed by 50%. An excellent opportunity to find out whether this affects the speed test bias.

If I can believe my internet service provider, my download speed has increased from 50 Mbps to 75 Mbps. However, through my testing, I know better. My download speed has increased from 56 Mbps to 84 Mbps!

Findings

Based on a new test (The ultimate speed test test 2021) and the results from the 2020 test, I come to the following findings (and conclude that the advice mentioned above is still valid).

SpeedOf.me (max) is almost unbiased

All speed tests have a negative bias. The negative bias of SpeedOf.me is almost zero. On average the bias of SpeedOf.me (based on the max download speed) is -0.4%.

Note that the standard deviation of SpeedOf.me is 0.1Mbps. This speed test is accurate and consistent.

Second best is Comparitech with an average bias of -2.4% and a standard deviaton of 0.9Mbps.

Third is LibreSpeed with an average bias of -3.4% and a standard deviation of 0.2Mbps.

Other speedtests are inaccurate

I can only conclude that almost every speed test is inaccurate (although they can be fairly accurate). Judge for yourself based on the findings of (well known) speed tests mentioned below.

  1. N Perf: bias -8.0%, standard deviation 0.1Mbps (that is as consistent as SpeedOf.me)
  2. TestMy.net: bias -8.9%, standard deviation 0.2Mbps
  3. Measurement Lab: bias -9.1%, standard deviation 0.2Mbps
  4. Open Speed Test: bias -5.3%, standard deviation 0.3Mbps
  5. SamKnows: bias -8.6%, standard deviation 0.3Mbps
  6. Google Fiber: bias -8.7%, standard deviation 0.3Mbps
  7. Ookla Speedtest: bias -10.5%, standard deviation 0.3Mbps
  8. Bandwidth Place: bias -17.0%, standard deviation 0.3Mbps
  9. Fast: bias -21.7%, standard deviation 5.4Mbps
  10. Toast: bias -16.6%, standard deviation 6.8Mbps. This is the largest standard deviation measured.

All you speed test questions answered

The following FAQs are based on the above test and previous speed test tests.

 

Quick links to other questions

Which speed test is best?

Speed tests

  1. What is an internet speed test?
  2. How to perform a speed test?
  3. Which speed test is most accurate?
  4. What is the fastest speed test?
  5. What is the speed test top 5?
  6. Can I trust the speed test of my ISP?
  7. What speed tests are available?

Factors affecting your internet speed

  1. Which factors have the greatest influence on your internet speed?
  2. Does the test server used affect my internet speed?
  3. Does the browser you use affect your internet speed?
  4. Does the operating system you use affect your internet speed?
  5. Do other running programs affect your internet speed?
  6. Does the Domain Name System (DNS) server you use affect your internet speed?
  7. Does using video streaming affect your internet speed?
  8. Does using TOR affect your internet speed?
  9. Does downloading files affect your internet speed?
  10. How does VPN use affect your internet speed?
  11. Does the hardware used affect my internet speed?
  12. How does malware affect my internet speed?
  13. Does the location of the Wi-Fi router matter?
  14. Does time of day affect Internet speed?
  15. How do other devices and users affect my internet speed?

Required speed

  1. How much internet speed is required?
  2. Which download speed is required for video streaming?
  3. Which download speed is required for gaming?
  4. Which internet speed is required for online meetings?

Speed tests

What is an internet speed test?

 

An internet speed test is a tool (website, app, program) that measures the maximum amount of data you can receive per second. This "downloadspeed" is expressed in megabits per second (Mbps).

How to perform a speed test?

 

Assuming you want to know the real download speed your ISP is providing, it is assumed that a wired computer is the best for an internet speed test. This is because Wi-Fi connections are not always reliable and not always as fast as the speed of a wired network. At the time of testing, you should be the only one using the Internet. Internet use of others can negatively influence the measurement. You should use the max. download speed of SpeedOf.me in a modern browser and make sure that there are no big downloads.

Speed determining factors

Which speed test is most accurate?

 

SpeedOf.me is the most accurate speed test there is when using the max. download speed.

The updated ultimate speed test test 2020Speed determining factors

What is the fastest speed test?

 

Internet Speed at a Glance is the fastest speed test there is.

The updated ultimate speed test test 2020

What is the speed test top 5?

 

Based on the criteria used for the ultimate speed test test this is the speed test top 5 of realistic speed tests:
(1) SpeedOf.me (when using the max. download speed)
(2) Comparitech
(3) LibreSpeed
(4) Speedsmart
(5) Internet Speed at a Glance

The updated ultimate speed test test 2020

Note that this list is very different from the curated top 5 based on different speed test comparisons.

Can I trust the speed test of my ISP?

 

More often than not, your ISP offers a speed test based on the Ookla Speedtest (a sample shows at least 5 out of 6). Such a mainstream speed test measures the download speed just as good as the Ookla Speedtest. The results of the Ookla Speedtest are structural significant lower than your real internet speed as measured by SpeedOf.me. Hence you might interpret the results of the speed test of your provider as a minimum speed you get.

The three categories of speed testsISP Speed tests

What speed tests are available?

 

There are numerous speed tests. This is mainly because many ISPs offer their own speed tests. However, these speed tests are not unique. Many ISP speed tests are based on the Ookla Speedtest. The number of unique speed tests is pretty clear. An overview of unique speed tests can be found at ZOMDir.

ISP Speed testsA shortlist of speed tests

Factors affecting your internet speed

Which factors have the greatest influence on your internet speed?

 

Large downloads (and TOR) have the biggest negative impact on your internet speed.

Speed determining factors

Does the test server used affect my internet speed?

 

The test server used does not affect your internet speed.

Depending on the speed test used, the test server used can affect the measured internet speed.

However, in most speed tests, the test server used does not significantly affect the measurement of your internet speed.

Speed determining factors (based on the first test)

Does the browser you use affect your internet speed?

 

As long as you use a modern browser (Chrome, Edge, Firefox), this will not affect your internet speed.

Speed determining factors

Does the operating system you use affect your internet speed?

 

As long as you are running a modern updated operating system (Linux, OS X, Windows), it will not affect your internet speed.

Speed determining factors

Do other running programs affect your internet speed?

 

Other active programs have no significant negative effect on your internet speed. However, intensive calculations can make it difficult to measure your internet speed properly.

Speed determining factors

Does the Domain Name System (DNS) server you use affect your internet speed?

 

The Domain Name System (DNS) server you are using will not affect your internet speed.

Speed determining factors

Does using video streaming affect your internet speed?

 

Video streaming uses some of your internet speed. Your internet speed as provided by your ISP does not change.

Depending on the speed test used, the use of video streaming can affect the measurement of your internet speed.

Speed determining factors

Does using TOR affect your internet speed?

 

TOR uses a lot of your internet speed. Your internet speed as provided by your ISP does not change.

If you measure your internet speed while using TOR, the measured speed will be significantly slower.

Speed determining factors (based on the first test)

Does downloading files affect your internet speed?

 

Downloading files uses some of your internet speed. Your internet speed as provided by your ISP does not change.

If you measure your internet speed while downloading files, the measured speed will be significantly slower.

Speed determining factors

How does VPN use affect your internet speed?

 

Depending on the VPN (Virtual Private Network) used, this can significantly affect your internet speed.

Research shows that there are major differences. There are VPNs that do not have a significant influence, but also VPNs that do have a significant influence.

Note that your internet speed as provided by your ISP does not change with the use of VPN.

Speed determining factors

Does the hardware used affect my internet speed?

 

The hardware you use (computer, Wi-Fi router, Powerline) can affect your internet speed.

This will be especially the case when the specifications of your hardware are less than the download speed provided by your ISP.

Note that the slowest part of your network determines your internet speed.

How does malware affect my internet speed?

 

The influence of malware on your internet speed cannot be determined generically. You can assume that malware is using some of your internet speed.

Hence, malware is likely to negatively impact your internet speed. How much that is depends on the malware on your system.

Does the location of the Wi-Fi router matter?

 

Wi-Fi uses a specific part of the radio frequency (RF) spectrum. Concrete, brick and masonry significantly dampen the radio signals used by Wi-Fi. The radio waves from a microwave oven interfere with Wi-Fi radio signals.

The location of your WiFi router can therefore greatly affect your internet speed.

Does time of day affect Internet speed?

 

The time of day can affect your internet speed. It depends on your internet subscription and the quality of your Internet Service Provider's (ISP's) network.

Wikipedia - Internet rush hour

How do other devices and users affect my internet speed?

 

Other devices and users will use some of the available internet speed. Your internet speed as provided by your ISP does not change.

If you measure your internet speed while other devices and users are using the internet, the measured speed may be slower.

This depends on the internet usage by the other devices and users.

Required speed

How much internet speed is required?

 

The required internet speed depends on the number of users and the type of use. As a rule of thumb, moderate use of the internet requires a download speed of 8 Mbps per user.

FCC's Household Broadband Guide

Which download speed is required for video streaming?

 

The required download speed for video streaming in HD (High Definition) television quality is 5 Mbps per screen. This requirement is independent of the streaming platform. The best speed test to check this required download speed is a conservative speed test like Fast. Note that Fast is provided by Netflix.

Netflix Internet Connection Speed RecommendationsWhat internet speed do I need for fire stick?You Tube's System requirementsThe three categories of speed tests

Which download speed is required for gaming?

 

Stadia and Xbox are gaming platforms with the highest internet speed requirements. These gaming platforms require a download speed of at least 10Mbps per user.
For the PlayStation 4, and the Nintendo Switch you need a download speed of 3Mbps.

Stadia Bandwidth requirementsXbox Cloud gaming

Which internet speed is required for online meetings?

 

It depends on the platform you use. For example Zoom requires 2Mbps up and down for a single screen. MS Teams requires 1Mbps up and 2Mbps down for a HD Group video calling (540p videos on 1080p screen).

System requirements for Zoom RoomsMS Teams' Bandwidth Requirements

Other questions

Do you have another question regarding speed tests, and you can't find the answer?

Please let me know by sending an e-mail to zomdir@gmail.com.