There is no countdown on this page and no deadline to beat. The only clock is a quiet count-up of elapsed time, and it is there because words per minute is a rate and a rate needs a number of minutes — not because anything runs out. Type for eight seconds or eight minutes, stop mid-sentence, and press Finish whenever you are done. Your live speed and accuracy update as you go, so you can watch a habit change in real time rather than waiting for a verdict at the end.
Warming up before a timed run. Learning a new keyboard layout, where speed is beside the point for the first week. Getting back into it after a break. And anyone the timer simply stresses — this page is the accommodation for that, deliberately, and it is a first-class mode rather than a lesser one. The timed test and the Road are there when you want a number; nothing here pushes you toward them.
Common words is a stream of the two hundred most ordinary English words, with no punctuation and no capitals — the band for building rhythm. Standard is full sentences with everyday punctuation, which is what most typing actually looks like. Advanced adds numerals, symbols, quotes and mixed case, the characters that real work contains and that most people are slowest at.