Fact · Typing and writing speed
40 to 70percent of keystrokes
In the 136 million keystroke study, slow typists used almost no rollover, while most fast typists used rollover on 40 to 70 percent of their keystrokes.
Checked against its source on October 16, 2026
In the source's own words
“Slow typists use nearly no rollover, whereas the majority of fast typists use rollover for 40–70% of keystrokes.”
Observations on Typing from 136 Million Keystrokes, Vivek Dhakal et al., CHI 2018, ACM Conference on Human Factors in Computing Systems, 2018, Abstract.
Open the original (DOI 10.1145/3173574.3174220)- What it measures
- Rollover means the next key goes down before the previous key comes up. The study used an online typing test with volunteers on their own computers, and its fast typists were those faster than 90 percent of participants.
- What it does not show
- The 40 to 70 percent range describes fast typists, not the average typist, whose rollover ratio was 25 percent. The sample is self-selected, so it shows what online test takers do, not every typist.