Reading rate, usually measured in words per minute, is a common operationalization of reading fluency in second language (L2) research and pedagogy. However, the impact of word length is often not addressed. This paper presents two studies showing how the number of characters in a text influences L2 reading time, independent of word counts, within classroom-based activities for Japanese university English as a Foreign Language students. In Study 1, students (N = 160) read two sets of graded texts manipulated to differ only in the total number of characters. The texts with more characters required significantly more time to read, with a small effect size. In Study 2, the average reading times for students (N = 27) throughout a semester-long timed reading course were strongly associated with text length as measured in characters, controlling for differences in word counts. Together these studies support the inclusion of character-based counting units when measuring L2 reading rate or reading amount.