2.3 Why you should use one space after each sentence

What this page is about

Each Basic Concept page has three sections:


This page asserts a very simple rule: press the spacebar only once at the end of each sentence.

This isn't too hard a concept to grasp. The question is: why?

Why not use two spaces?

After all those years of using a typewriter, and learning to put two spaces after every sentence, why should I change?

There are two reasons.

  • The first reason is because typewriters traditionally use non-proportional fonts. Typewriter fonts generally look like this one.  Every character is the same width. Consider a word like illumination.  A lower-case l or i takes up the same space as an m or even M.
  • Because they use non-proportional fonts, our minds can separate the sentences easily only if there is quite a lot of space between the sentences.
  • But when you use a word processing program, like Word, you generally use proportionally spaced fonts. So in a word like "illumination", i's and l's are much skinnier than an m. Because the letters aren't spaced out so much, our minds can cope with less space between sentences. And text in proportional fonts with an extra space at the end of the sentence looks too chopped up.
  • The other reason is that some people like to justify text. That means that Word will put little spaces between the words to stretch out the text so that the right-hand margin is straight. This paragraph is justified, to demonstrate. Publishers typeset most books justified. Word obviously uses quite complex maths to work out how to stretch each line so that the right-hand margin is even. If you have extra spaces in the middle of sentences, Word stretches the text in each line and includes your "extra" spaces as well. The result can look very ugly.

So: when using Word, use one space at the end of every sentence.


When using a word processor such as Word, you only need to press the spacebar once after each sentence.

Curiosity Shop: More about using the spacebar

  • To read more about the "one space or two" question, see the following articles on the web from a variety of different kinds of sites:
    • Chicago Manual of Style (aka the style bible!)
    • Manuscript format for publication in Fruit Gardener [Lene Fredborg, 1-Dec-2020: Removed outdated link to http://www.crfg.org/fg/copydline.html]
    • [NOTE: outdated link removed by Lene Fredborg 12-Jul-2016] One Versus Two Spaces After a Period
    • [NOTE: outdated link removed by Lene Fredborg 06-Aug-2021] Get it write: One or two spaces after a period?
  • If you use Word to create pages for the web, don't bother exercising your thumbs by typing more than one space. Why? Because Web pages ignore two spaces in a row, and display only one, no matter how many spaces you type!