Glossary
Characters per minute (CPM)
Characters per minute (CPM) is the number of characters typed in one minute, counting spaces and punctuation. Words per minute is the same count divided by five, so a typist at 50 WPM enters 250 characters per minute.
Updated October 16, 20265 cited facts, each traced to its source
Also called CPM, strokes per minute.
Characters per minute (CPM) is a typing speed counted in characters rather than words. Every key that produces a character counts, including the space bar and punctuation, and the number is taken over one minute.
Entry speed is characters divided by time
Text entry research counts speed in characters. I. Scott MacKenzie's note on calculating text entry speed defines it simply: "Entry speed is simply the total number of characters entered divided by the time to enter them" 1. MacKenzie's own unit is characters per second, so a CPM figure is the same measure multiplied by 60.
The note also explains that the start and end of the timer change the result. If the clock starts at the first character, the time spent preparing that first keystroke is left out, so researchers must state exactly where they measured.
CPM converts to WPM with a five-character word
Most typing tests report words per minute, and they convert from characters with a fixed rule: one word is five characters long, including spaces 2. So CPM is five times WPM. A typist at 50 WPM enters 250 characters per minute 3, and the two units always move together.
Why CPM is useful
CPM is more precise than WPM for text where words are not natural units. A string of numbers, a password, source code or a list of symbols has no word boundaries, so counting characters gives a fairer measure of how fast a person can enter it. Researchers use the same idea when they compare two entry methods: they count what was entered, not how many words a passage happens to contain.
CPM is also a useful check on words per minute. If you know your character count, you can see whether a test used the five-character convention or counted real words.
What CPM does not show
CPM counts the characters a person types, so it does not tell you whether those characters are correct. A fast CPM with many errors is not a good result, which is why speed is always reported beside typing accuracy. CPM also does not separate the time spent correcting errors from the time spent writing new text, unless the test records each keystroke, as MacKenzie's method does.
How CPM relates to dictation
Dictation is usually discussed in words per minute, because normal speech runs at 125 to 150 words per minute 4. Converting to characters shows the same comparison in units that match a keyboard. In a controlled iPhone study, English entered by speech reached 153 words per minute against 52 on the keyboard 5, and the gap in characters is the number that matters when you choose how to write.
Related terms
- Words per minute (WPM): the word-based unit that most tests report.
- Keystrokes per hour (KPH): a count of key presses over an hour, used for data entry.
- Keystrokes per character (KSPC): how many key presses it takes to produce one character.
Guides and questions that cover it
Evidence
Every number on this page, with where it comes from. Open a fact to see the exact words in its source.
- 1.
- 2.
- 3.A typist at 50 words per minute enters 250 characters per minute, because one word counts as five characters.
Calculated from 1 other fact
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- 5.
Related terms
- Typing Speed: Average WPM and How to Type FasterThe topic this term belongs to
- Articulation rateArticulation rate is the number of syllables a speaker produces per second, leaving out pauses. It measures how fast the speech itself comes out, so it is usually faster than the overall speaking rate that counts every pause.
- ColemakColemak is an alternative English keyboard layout, introduced in 2006 and designed for efficient, comfortable touch typing. Its supporters describe it as the third most popular layout for English touch typing, after QWERTY and Dvorak, but that ranking has no stated method.
- Dvorak Simplified KeyboardThe Dvorak Simplified Keyboard is an alternative English keyboard layout that places the most common letters on the home row. Dvorak and Dealey applied for a patent on it in 1932, but the studies that claimed it was faster than QWERTY have been criticized, and the evidence for a speed gain is weak.
- Home rowThe home row is the middle row of keys on a keyboard, where the fingers rest when you touch type. On a QWERTY keyboard it holds A, S, D, F for the left hand and J, K, L and semicolon for the right, and every other key is reached by moving a finger away from it and back.
- Hunt and peckHunt and peck is a typing method in which the typist finds each key by sight and presses it with one or two fingers, usually the index fingers. It is also called two-finger typing, and it differs from touch typing, which relies on memorized key positions and the home row.
- Keystroke dynamicsKeystroke dynamics is the identification of a person from the rhythm of their typing, using the timing between key presses as a pattern much like a handwritten signature. It is a behavioral biometric, so it supports identity checks through statistical matching rather than proving who typed.
- Keystrokes per character (KSPC)Keystrokes per character (KSPC) is the average number of keystrokes a text entry method needs to produce one character of text. A basic QWERTY keyboard scores 1, methods that need more presses score above 1, and word prediction can score below 1.
- Keystrokes per hour (KPH)Keystrokes per hour (KPH) is the number of key presses made in one hour. It is the standard unit for numeric data entry, where many jobs require 8,000 or 10,000 keystrokes per hour, and it counts keys rather than words.
- Oral reading fluency (ORF)Oral reading fluency (ORF) measures how many words a reader gets right in one minute of reading a passage aloud. Schools record the result as words correct per minute (WCPM), which subtracts the words read wrongly from the total.
- QWERTYQWERTY is the standard letter arrangement on English keyboards, named for the first six letters of the top row. Christopher Latham Sholes devised it in the early 1870s for typewriters, and it is still the layout most people type on, even though faster layouts have been proposed.
- Rollover typingRollover, or key rollover, is the number of key presses a keyboard can detect when they overlap. Two-key rollover reliably detects only two keys at once, and a matrix keyboard without diodes can register a ghost key when three keys are pressed together.
- StenotypeA stenotype, also called a steno machine, is a chorded keyboard that stenographers use for shorthand, pressing several keys together to produce a syllable or word. The NCRA's court reporter skills test sets a speed of 225 words per minute, and voice writing is a newer method that uses speech recognition instead.