Fact · Typing and writing speed
Wikipedia says a keyboard with two-key rollover can reliably detect only two keys used at the same time.
Checked against its source on October 16, 2026
In the source's own words
“A keyboard with "two-key rollover" can reliably detect only any two keys used simultaneously”
Key rollover (Wikipedia), Wikipedia, 2026, Limited key rollover.
Open the original- What it measures
- The same section gives the typing consequence: a third key pressed while two are held is not reliably detected.
- What it does not show
- The article describes the design in general terms and does not say how common two-key rollover is today.