The Origins and Math of "Words Per Minute"
In the English language, words vary dramatically in length—from single-letter words like "a" or "I" to polysyllabic words like "internationalization". If a test measured literal space-separated words, a typist transcribing short conversational text would score significantly higher than one typing scientific or legal literature.
To solve this inconsistency, typewriter manufacturers and the International Federation for Information Processing (IFIP) established the universal standard in the early 20th century:
The Universal 5-Character Standard
One standardized "word" is defined as exactly 5 keystrokes, which includes letters, spaces, digits, and punctuation marks.
Standard WPM = (Total Correct Characters / 5) ÷ Elapsed Minutes