JS Tip 478: Use One Space after a Period (Despite the Recent Study)

From the Writing Workshops: Use One Space After a Period (Despite the Recent Study)

Use one space after a period (or other sentence-ending punctuation).

Here we stand with the Associated Press, the Modern Language Association, and The Chicago Manual of Style. One space.  

Period. Well. Yes. Period.  

A recent study in the journal Attention, Perception, & Psychophysics claimed that two spaces were better. 

But the study was flawed. (The research team recognized the flaws but persisted anyway.)

The study used a monospaced font (Courier New) to test the theory. 

Wait a minute. 

Typewriters used monospaced fonts. An i took up the same space as an m(because the typewriter was a mechanical system). You needed two spaces to identify the end of one sentence and the beginning of another. 

But when was the last time you used a typewriter? 

Word-processing programs use proportionally spaced fonts. 

Word-processing programs insert—automatically—the appropriate space between sentences. You don’t have to hit two spaces. (In fact, many spell-check and auto-correct programs will remove the extra space.) 


Use one space after a period (or other sentence-ending punctuation). One space is standard in business and technical writing.   

The study was flawed. Time Magazine ended its short report on the study with “Time stands by its one-space stance.”


Mark Brooks