10fastfingers.com

I find myself more often than not listening to my favorite song on repeat while I type. When it's playing, I just focus on the song and I end up typing faster and more accurately than I do any other time.

What exactly are you typing? In the case of speedtests, I always switch off any music because it distracts me quite a bit, but while chatting, that a speedup caused by music well be the case (I'm usually programming, so I can't really measure any gain there...)

I'm just referring to typing tests and stuff while on the website.

For me it usually depends how much noise there is in the background. If there are people talking and whatnot, putting music on drones it out and helps me concentrate. If it's silent then I usually type best when I'm just listening to the tapping of the keys. Something about listening to the button taps helps me maintain a steady rhythm.

I have noticed many times that listening to something else while typing can increase my speed on an unfamiliar test. The reason is fairly obvious. If you are focusing too much on the content of the text, you tend to slow down or stumble. If your attention is directed elsewhere, your muscle memory can then take over.