Color blindness and speed tests

TL;DR

All speed tests mentioned in top 10 of speed tests are usable for all types of color blindness.

 

Contents

  1. Introduction
  2. Method of measurement
  3. Speed tests to test
  4. The measurements
  5. Conclusions
 

Introduction

Color contrast is one of the top 10 website accessibility issues mentioned in this Top Ten Most Common Web Accessibility Issues. Hence the question is, how usabale are speed tests for users with color blindness.

The most common type of color blindness is red-green color blindness. Of the four types of red-green color blindness deuteranomaly is the most common type of red-green color blindness.

For this color blindness test, we use the WCAG Color contrast checker extension for Google Chrome to test the color schemes used by the most popular speed tests.

 

Method of measurement

For this test we visit the homepage of the speed test and modify the used color palette for the 8 types of color blindness (protanopia, protanomaly, deuteranopia, deuteranomaly, tritanopia, tritanomaly, achromatopsia and achromatomaly).

The test is invoked immediately after loading the homepage. For some speed tests it is necessary to accept the cookies before the extension works. These speed tests are: meter.net and testmy.net When a speed test starts automatically, the test is started when the test is completed.

For this test intially the number of checked elements is counted without a color blindness filter. Subsequently, for each type of color blindness, it is checked whether the number of checked elements has decreased. If so, this form of color blindness is noted.

As a double check, it is manually (subjectively) assessed whether the speed tests can be used for all forms of color blindness.

 

Speed tests to test

For this test we test the speed tests mentioned in the top 10 of best speed tests. The test is done for WCAG level AA.

Note that speed tests which support light mode and dark mode are tested twice. Once with the light mode theme and once with the dark mode theme.

 

The measurements

  1. Cloudflare tritanopia (5 instead of 7 -out of 11- checkmarks)
  2. Fast deuteranopia, tritanopia (both 5 instead of 6 -out of 9- checkmarks)
  3. Google Fiber tritanopia, tritanomaly (both 6 instead of 7 -out of 11- checkmarks)
  4. Internet Speed at a Glance (Light mode) tritanopia (4 instead of 6 -out of 7- checkmarks)
  5. Internet Speed at a Glance (Dark mode) protanopia (5 instead of 6 -out of 7- checkmarks), deuteranopia (4 checkmarks)
  6. M-Lab protanopia, protanomaly, deuteranopia, deuteranomaly, tritanomaly (all 5 instead of 6 -out of 14- checkmarks), tritanopia (4 checkmarks)
  7. Meter.net (Light mode) protanopia, protanomaly, tritanopia (all 22 instead of 23 -out of 25- checkmarks), deuteranopia (21 checkmarks)
  8. Meter.net (Dark mode) achromatopsia, achromatomaly (both 23 instead of 24 -out of 25- checkmarks)
  9. Ookla Speedtest protanopia (14 instead of 18 -out of 19- checkmarks), protanomaly (16 checkmarks), deuteranopia (13 checkmarks)
  10. SpeedOf.me tritanopia, tritanomaly (both 14 instead of 15 -out of 39- checkmarks)
  11. SpeedSmart (Light mode) tritanopia (14 instead of 15 -out of 22- checkmarks)
  12. SpeedSmart (Dark mode) tritanopia, tritanomaly, achromatomaly (all 15 instead of 16 -out of 23- checkmarks)
  13. TestMy.net (Light mode) protanopia, protanomaly, deuteranopia, deuteranomaly, tritanopia, tritanomaly, achromatopsia (all 13 instead of 14 -out of 19- checkmarks)
  14. TestMy.net (Dark mode) protanopia, protanomaly, deuteranopia, deuteranomaly, achromatopsia (all 11 instead of 13 -out of 17- checkmarks), achromatomaly (12 checkmarks)

Some examples

In the image below, you see the Google Fiber speed test with several simulations of color blindness (None, tritanomaly, tritanopia, protanopia and achromatopsia).

Some examples Google Fiber with several simulations of color blindness

Subjective assessment

The measurements above makes it very hard to draw conclusions, hence I decided to judge for myself whether the speed test is useful with the various limitations.

Before doing this I made and passed the EnChroma® Color Blindness Test.

No usability issues were found for any of the speed tests tested for all types of color blindness (light and dark mode).

 

Conclusions

All speed tests tested are usable for all types of color blindness.