How is WPM calculated in this typing test?
WPM is calculated by dividing the passage's word count by the time taken (in seconds), then multiplying by 60. Some typing tests instead use a character-based method - total characters typed divided by 5, since 5 characters is treated as one standard 'word' - which can produce a slightly different number for the same passage, since real words vary in length. Either method gives a reasonable estimate; they just count differently.