One Space or Two? That Recent Study Won’t Tell You.

A recently released study tested whether it was better to put one space or two spaces after a period. A commenter at Kieran Healy’s Twitter feed comments:

I guess this confusion isn’t surprising, but the “rule” has never changed. It’s always been two spaces for monospaced fonts, like the ones on typewriters, and one space for proportional fonts, like the one you’re reading now. There was good reason for this:

  • Monospaced fonts like this one already have a lot of air.  Two spaces make it easier to quickly distinguish when a new sentence begins.
  • Proportional fonts like this one are denser and don’t have that problem. Spaces and capital letters jump out at you.

More to the point, proportional text in magazines, books, and newspapers is usually justified on both right and left—like this paragraph. When text is justified, typesetting equipment ignores your spaces entirely, putting in just enough to make the line lengths come out right. So it doesn’t really matter what you do.

Still, what about the study? As it turns out, the authors tested only monospaced fonts, which is odd since almost no one uses them anymore. Here’s an excerpted and colorized version of their main result:

Among people who preferred one space, reading speed was about 5 wpm higher with one space. Among people who preferred two spaces, reading speed was about 9 wpm higher with two spaces. In other words, people preferred whatever they preferred, and the difference wasn’t very much anyway.

Oddly, though, the folks who preferred two spaces were generally faster readers than those who preferred one space. For $39 I suppose I could find out if the authors had anything to say about this. However, I suspect it means that the difference between the two groups isn’t random.

So the whole study is pretty useless.  What would be more interesting would be a study of proportional fonts.  Over the past couple of decades, it’s become far more common to use a ragged right margin, like the one you’re reading now.  The reason is readability: By keeping the spacing constant, instead of tweaking it to make the line lengths come out evenly, the text is easier to read.  But with even spacing, would two spaces after a period make the text even easier to read?  I don’t know!  Someone should do a study to find out.

THE TRUTH...

is the first thing despots go after. An unwavering commitment to it is probably what draws you to Mother Jones' journalism. And as we're seeing in the US and the world around, authoritarians seek to poison the discourse and the way we relate to each other because they can't stand people coming together around a shared sense of the truth—it's a huge threat to them.

Which is also a pretty great way to describe Mother Jones' mission: People coming together around the truth to hold power accountable.

And right now, we need to raise about $400,000 from our online readers over the next two months to hit our annual goal and make good on that mission. Read more about the information war we find ourselves in and how people-powered, independent reporting can and must rise to the challenge—and please support our team's truth-telling journalism with a donation if you can right now.

payment methods

THE TRUTH...

is the first thing despots go after. An unwavering commitment to it is probably what draws you to Mother Jones' journalism. And as we're seeing in the US and the world around, authoritarians seek to poison the discourse and the way we relate to each other because they can't stand people coming together around a shared sense of the truth—it's a huge threat to them.

Which is also a pretty great way to describe Mother Jones' mission: People coming together around the truth to hold power accountable.

And right now, we need to raise about $400,000 from our online readers over the next two months to hit our annual goal and make good on that mission. Read more about the information war we find ourselves in and how people-powered, independent reporting can and must rise to the challenge—and please support our team's truth-telling journalism with a donation if you can right now.

payment methods

We Recommend

Latest

Sign up for our free newsletter

Subscribe to the Mother Jones Daily to have our top stories delivered directly to your inbox.

Get our award-winning magazine

Save big on a full year of investigations, ideas, and insights.

Subscribe

Support our journalism

Help Mother Jones' reporters dig deep with a tax-deductible donation.

Donate