Does a speed test need JavaScript?

TL;DR

Yes, modern speed tests require JavaScript.

2 Speed tests don't need JavaScript, however their results are strongly deviating from the advertised speed. These speed tests are not recommended.

5 Out of the 27 tested speed tests that need JavaScript, informs the user that JavaScript is required. Of these speed tests, only Internet Speed at a Glance made it to the top 10.

Contents

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

Introduction

Almost every modern speed test states that it is an HTML5 based speed test. What is not always clear is whether JavaScript is required.

1. Bandwidth Place (...) a browser-based, HTML5 speed test (...)
2. Cloudflare's speed test (...) The public-facing static content (HTML, CSS, JavaScript, images) is stored in Workers KV (...)
3. Fireprobe (...) test your Internet connection speed (download, upload) and quality (ping, jitter) using the most accurate HTML5 tool in any web browser (...)
4. Internet Speed at a Glance (...) Note that this speed test requires JavaScript (...)
5. Open Speed Test (...) JavaScript and HTML5 technology (...)
6. SpeedOf.me (...) SpeedOf.Me (Speed of me), is a pure HTML5/JavaScript speed test which relies only on browser core technologies. (...)
7. TestMy.net, tab "What makes TMN different?" (...) TestMy.net is the first and only truly accurate HTML5 & PHP driven speed test online (...)

In this test, we test if JavaScript is required for a speed test.

Method of measurement

For this test the Firefox browser is used in combination with the NoScript Security Suite extension.

Speed tests to test

Because this is a very simple test, all unique speed tests as collected at ZOMDir will be tested.

The measurements

1. Bandwidth Place need JavaScript, but does not inform the user
2. Bredbandskollen need JavaScript and informs the user
3. Broadband Internet Speed test (Gone) works without JavaScript
4. Broadband Speed Checker need JavaScript, but does not inform the user
5. Cloudflare need JavaScript, but does not inform the user
6. CloudHarmony (Gone) need JavaScript, but does not inform the user
7. Comparitech need JavaScript, but does not inform the user
8. DSLReports need JavaScript and informs the user
9. Fast need JavaScript, but does not inform the user
10. Fireprobe need JavaScript, but does not inform the user
11. Google Fiber need JavaScript, but does not inform the user
12. Internet Speed at a Glance need JavaScript and informs the user
13. LibreSpeed need JavaScript, but does not inform the user
14. Measurement Lab need JavaScript, but does not inform the user
15. Meter.net need JavaScript, but does not inform the user
16. N Perf need JavaScript, but does not inform the user
17. Ookla Speedtest need JavaScript, but does not inform the user
18. Open Speed Test need JavaScript, but does not inform the user
19. RCN Speedtest (now redirected to Astound) need JavaScript, but does not inform the user
20. SamKnows need JavaScript and informs the user
21. SpeedCheck need JavaScript, but does not inform the user
22. SpeedOf.me need JavaScript, but does not inform the user
23. SpeedOf.me API Sample Page need JavaScript, but does not inform the user
24. SpeedSmart need JavaScript, but does not inform the user
25. Speedtest4.PHP works without JavaScript
26. TestMy.net need JavaScript, but does not inform the user
27. Toast need JavaScript, but does not inform the user
28. Which Broadband Speed Test need JavaScript, but does not inform the user
29. Xfinity xFi Speed Test need JavaScript and informs the user

Conclusions

There are two speed test which don't require JavaScript. However these speed tests are not recommended because the results doesn't make sense. All other speed tests need JavaScript.

The following speed tests informs the user that JavaScript is required:

1. Bredbandskollen
2. DSLReports
3. Internet Speed at a Glance
4. SamKnows
5. Xfinity xFi Speed Test

Of these speed tests, only Internet Speed at a Glance made it to the top 10.

Broadband Internet Speed test

With an advertised speed of 100 Mbps, the Broadband Internet Speed test measures 11933 kbps. That is 12 Mbps. This value is so different from the speed to be measured that this speed test is not recommended.

Speedtest4.PHP

The Speedtest4.PHP speed test measures 275379.318 kbps. That is 275 Mbps. Again, this value is so different from the speed to be measured (100 Mbps) that this speed test is not recommended.