How Many Spaces Go at the End of a Sentence?

How Many Spaces Go at the End of a Sentence

One Space? Two Space? Red Space? Blue Space?: The One Space/Two Space Debate

For the last 500 and some odd years, since Johannes Gutenberg’s invention of moveable type, typographers have been arguing about the rules for  printing our favorite reading materials. It wasn’t until the invention of the typewriter in 1868, however, that we, the typing laity, began to debate when and how we should follow different typological rules.

Chances are that, at some point, especially if you’re over 30, when you’ve asked how many spaces go at the end of a sentence, you’ve heard someone, most likely a professor or teacher, say that you should put two spaces after at the end of a sentence. And then you’ve heard someone else, perhaps equally educated and intelligent, say that you are doing it wrong there should only be one space after each sentence.

So, how many spaces go at the end of a sentence? One or two?

The debate around this question is murky and complicated. It involves the history of typography, the typewriter, style guides, and publishing. It is probably one of the biggest debates devoted to whitespace on the internet, other than the great spaces vs. tabs debate, of course.

Here’s a list of some of the different facets to the one space vs. two space debate:

  1. Monospaced font– The reason for the proliferation of the idea that two spaces should be at the end of a sentence comes from monospaced font. Essentially, monospaced fonts take up an equal amount of horizontal space for each letter. So, for example, in monospaced fonts, “I” and “W” take up the same amount of space, even though they each take up much different widths of their respective space. This means that the “I” will have quite a bit of white space between letters and “W” will have very little (monospaced fonts are rarely used anymore- Courier or Courier New are the most popular monospaced fonts still in use). The reason that monospaced fonts were used was because typewriters’ striker arms were all the same width. So that means that if you only put one space at the end of a sentence, and the next sentence started with a “W” then the period and the “W” would be extremely crammed together. Since we are no longer under the constraints we using typewriters, why would you put two?
  2. Mass market publications- In the 1940s and 50s mass market publications, such as magazines and pulp novels, adopted the single spacing after publishers realized that one space after a sentence was obviously much more cost-effective. Why take up valuable page space for bank space? Seems like a no-brainer.
  3. IBM’s Executive Typewrtiter- In 1941, IBM introduced the Executive Typewriter, which broke the monospaced grids into fifths, allowing for proportional fonts on typewriters. Even after the computer supplanted the typewriter, they continued to use monospaced font for a while. However, For the last 30 years or more, all computers have been able to produce proportional fonts.
  4. Proportional fonts predate typewriters– Typesetters have been using proportional fonts since at least the 19th century. So, the idea that monospaced fonts were always used by typesetters is a bit of a misnomer.
  5. Style guides have no real consensus– Ok, they sort of have a consensus about how many spaces go at the end of a sentence. According to the Chicago Manual of Style, you should use one space; the Modern Language Association says you should use one space, but it also says that two is acceptable; The American Psychological Association suggests two for drafts but one for publications. So, while there is no precise consensus about when to use one space, all of the major style guides agree that one space is appropriate.

The answer to how many spaces go at the end of a sentence is unequivocal at this point: you only need one space at the end of a sentence.

So, unless whomever you’re writing for demands that you put two spaces at the end of your sentences, DON’T. PERIOD. If you’re super old school and just can’t seem to break the habit, at least use two spaces consistently . . . sigh . . .but, honestly, you should really just get with the times. 



Matthew Groner
About Matthew Groner 21 Articles
Matthew Groner is a Staff Writer for Sporcle. He enjoys foraging for gourmet mushrooms and calculating the odds of the Kansas City Chiefs winning a Super Bowl in his lifetime.