One Space or Two Spaces After the Period at the End of the Sentence?


I decided to do a little research about that pesky question of whether to use one or two spaces after the period at the end of a sentence. As a lifelong proponent of the two spaces camp, I now grudgingly yield to the 21st century and advances in typography to move to using only one space after the period.

Every major style guide–including the “bibles” of the Modern Language Association Style Manual and the Chicago Manual of Style–prescribes a single space after a period. The two-space rule began during the age of typewriters, when the spacing of letters was not proportional (as it is now) and using two spaces at the end of a sentence made documents more readable. The only computer font that is not proportional is Courier, which we do not use. (I don’t think anyone uses it anymore.)

According to an article in Slate ( which addressed this very issue, “because we’ve all switched to modern fonts, adding two spaces after a period no longer enhances readability, typographers say. It diminishes it.” This same point was made by every major source that I researched.

So, I am waving the white flag of surrender in my ancient, Tyrannosaurus Rex hands to say that I think the switch to one space is the better and updated rule to follow.

I feel I can adapt to change okay, however, if you find yourself having great difficulty in making this transition, I saw the following suggestion in the online version of the Chicago Manual of Style: once the document is finished, use the Find and Replace feature to eliminate all double spaces. In the “Find” box, type two spaces, and in the “Replace With” box, type one space. Hit “Replace All” and you’re done.

R. Lynn Archie