TL;DR
In general, a valid web page is more likely to be accessible through all types of browsers, platforms, and screen readers.
Two speed tests have zero validation errors, these speed tests are Internet Speed at a Glance and SpeedOf.me API Sample Page.
Second best (with 1 validation error) are Cloudflare and Ookla Speedtest.
Contents
Introduction
In general, a valid web page is more likely to be accessible through all types of browsers, platforms, and screen readers. That is why we test all speed tests on valid HTML code.
Method of measurement
For this test we test the homepage of with W3C's Markup Validation Service.
The test is invoked immediately after loading the homepage.
For this test we count the number of errors, warnings and info messages per homepage.
Speed tests to test
Because this is a relative simple test, the unique speed tests as collected at ZOMDir will be tested.
The measurements
- Astound speedtest 8 errors, 14 warnings and 0 info messages
- Bandwidth Place 84 errors, 81 warnings and 44 info messages
- Bredbandskollen 4 errors, 15 warnings and 18 info messages
- Broadband Internet Speed test (Gone) 7 errors, 12 warnings and 2 info messages
- Broadband Speed Checker 82 errors, 4 warnings and 0 info messages
- Cloudflare 1 error, 1 warning and 19 info messages
- Comparitech 10 errors, 9 warnings and 23 info messages
- DSLReports 161 errors, 21 warnings and 6 info messages
- Fast 90 errors, 1 warning and 41 info messages
- Fireprobe 71 errors, 6 warnings and 118 info messages
- Google Fiber 2 errors, 2 warnings and 0 info messages
- Internet Speed at a Glance 0 errors, 0 warnings and 25 info messages
- LibreSpeed 3 errors, 1 warnings and 18 info messages
- M-Lab 2 errors, 6 warnings and 3 info messages
- Meter.net 8 errors, 18 warnings and 39 info messages
- N Perf 21 errors, 8 warnings and 70 info messages
- Ookla Speedtest 1 error, 13 warnings and 43 info messages
- Open Speed Test 16 errors, 10 warnings and 11 info messages
- SamKnows 15 errors, 24 warnings and 1 info message
- SpeedCheck 33 errors, 32 warnings and 73 info messages
- SpeedOf.me 2 errors, 3 warnings and 17 info messages
- SpeedOf.me API Sample Page 0 errors, 4 warnings and 12 info messages
- SpeedSmart 28 errors, 7 warnings and 43 info messages
- Speedtest4.PHP Sorry! This document cannot be checked, because on line 1 it contained one or more bytes that I cannot interpret as utf-8 (in other words, the bytes found are not valid values in the specified Character Encoding)
- TestMy.net 18 errors, 1 warning and 59 info messages
- Toast 104 errors, 27 warnings and 18 info messages
- Which Broadband Speed Test 37 errors, 6 warnings and 13 info messages
- Xfinity xFi Speed Test 7 errors, 3 warnings and 1 info message
Conclusions
Based on the above measurements, we conclude that:
- The minimum number of errors is 0
- The maximum number of errors is 161
- The average number of errors is 30
- The median of the number of errors is 10
- The minimum number of warnings is 0
- The maximum number of warnings is 81
- The average number of warnings is 12
- The median of the number of warnings is 7
- The minimum number of info messages is 0
- The maximum number of info messages is 118
- The average number of info messages is 27
- The median of the number of info messages is 18
If we group the speed tests by the number of errors they have, we get the following list:
- 0 errors: Internet Speed at a Glance and SpeedOf.me API Sample Page
- 1 error: Cloudflare and Ookla Speedtest
- 2 errors: Google Fiber, SpeedOf.me and M-Lab
- 3 to 5 errors: LibreSpeed and Bredbandskollen
- 6 to 10 errors: Xfinity xFi Speed Test, Broadband Internet Speed test (Gone), Astound speedtest, Meter.net and Comparitech
- 11 to 20 errors: SamKnows, Open Speed Test and TestMy.net
- 21 to 50 errors: N Perf, SpeedSmart, SpeedCheck and Which Broadband Speed Test
- 51 to 100 errors: Fireprobe, Broadband Speed Checker, Bandwidth Place and Fast
- 101 plus errors (and not testable): Toast, DSLReports and Speedtest4.PHP