[jedberg]

That test was totally inaccurate for me. It got the download right but upload was only 1/12 of my rated speed and 1/12 of what all the other tests (and my actual experience) tell me.

[archb]

Same for me. The download speed was fine, but upload speed was 1.75x the actual one.

[girvo]

Same for me: download was okay, upload was completely wrong

[steve_adams_86]

My very limited experience in this space is that measuring uploads is actually quite a bit trickier and harder to nail down than download speeds

[arikrahman]

Perhaps you can audit the https://github.com/openspeedtest/Speed-Test codebase