one space between sentencesAlways one—
never two

Some top­ics in this book will of­fer you choic­es. Not this one.

Al­ways put ex­act­ly one space be­tween sentences.

Or more gen­er­al­ly: put ex­act­ly one space af­ter any punctuation.

Here’s a para­graph with one space be­tween sentences:

I know that many peo­ple were taught to put two spaces be­tween sen­tences. I was too. But these days, us­ing two spaces is an ob­so­lete habit. Some say the habit orig­i­nat­ed in the type­writer era. Oth­ers be­lieve it be­gan ear­li­er. But guess what? It doesn’t mat­ter. Be­cause ei­ther way, it’s not part of to­day’s ty­po­graph­ic prac­tice. If you have to use a type­writer-style font, you can use two spaces af­ter sen­tences. Oth­er­wise, don’t.

Now the same para­graph, but with two spaces be­tween sentences:

I know that many peo­ple were taught to put two spaces be­tween sen­tences.  I was too.  But these days, us­ing two spaces is an ob­so­lete habit.  Some say the habit orig­i­nat­ed in the type­writer era.  Oth­ers be­lieve it be­gan ear­li­er.  But guess what?  It doesn’t mat­ter.  Be­cause ei­ther way, it’s not part of to­day’s ty­po­graph­ic prac­tice.  If you have to use a type­writer-style font, you can use two spaces af­ter sen­tences.  Oth­er­wise, don’t.

See the prob­lem? In the sec­ond para­graph, the ex­tra spaces dis­rupt the bal­ance of white space. Mul­ti­plied across a whole page, rivers of white space can appear.

And one more time, in a type­writer-style font, the one case where two spaces are tol­er­a­ble (though still unnecessary):

I know that many peo­ple were taught to put two spaces be­tween sen­tences.  I was too.  But these days, us­ing two spaces is an ob­so­lete habit.  Some say the habit orig­i­nat­ed in the type­writer era.  Oth­ers be­lieve it be­gan ear­li­er.  But guess what?  It doesn’t mat­ter.  Be­cause ei­ther way, it’s not part of to­day’s ty­po­graph­ic prac­tice.  If you have to use a type­writer-style font, you can use two spaces af­ter sen­tences.  Oth­er­wise, don’t.

I have no idea why so many writ­ers re­sist the one-space rule. If you’re skep­ti­cal, pick up any book, news­pa­per, or mag­a­zine and tell me how many spaces there are be­tween sentences.

Cor­rect—one.

by the way

Still skep­ti­cal? You’re not alone. For rea­sons un­clear, this ad­vice pro­vokes un­usu­al con­tro­ver­sy. The ob­jec­tions sort out into these ma­jor themes:

You made up this so-called rule.

No. One space is the cus­tom of pro­fes­sion­al ty­pog­ra­phers and the con­sen­sus view of ty­pog­ra­phy au­thor­i­ties. No one has yet shown me con­trary au­thor­i­ty. For instance—

“Use a sin­gle word space be­tween sen­tences. … Your typ­ing as well as your type­set­ting will ben­e­fit from un­learn­ing [the] quaint Vic­to­ri­an habit” of us­ing two spaces be­tween sentences.

Robert Bringhurst, The El­e­ments of Ty­po­graph­ic Style (ver­sion 3.1), p. 28.

“The type­writer tra­di­tion of sep­a­rat­ing sen­tences with two word spaces af­ter a pe­ri­od has no place in typesetting.”

James Fe­li­ci, The Com­plete Man­u­al of Ty­pog­ra­phy, p. 80.

“Chica­go ad­vis­es leav­ing a sin­gle char­ac­ter space, not two spaces, be­tween sen­tences and af­ter colons used with­in a sen­tence … .”

The Chica­go Man­u­al of Style (16th ed.), rule 2.9.

I think two spaces look bet­ter so that’s what I’m go­ing to use.

I’m telling you the rule. If you want to put per­son­al taste ahead of the rule, I can’t stop you. But per­son­al taste doesn’t make the rule evap­o­rate. It’s like say­ing “I don’t like how sub­junc­tive-mood verbs sound, so I’m nev­er go­ing to use them.”

I’m ac­cus­tomed to see­ing two spaces be­tween sentences.

Are you? All the pro­fes­sion­al­ly type­set ma­te­ri­als you read use one space be­tween sentences.

I learned to type on a type­writer, and at this point I’m phys­i­cal­ly un­able to do any­thing but type two spaces.

When you moved from the type­writer to the com­put­er, you had to learn to type a car­riage re­turn at the end of each para­graph, rather than the end of each line. How is this any different?

Every­one I work with uses two spaces.

A core prin­ci­ple of this book is that your doc­u­ments are gov­erned by the same rules of ty­pog­ra­phy as any pro­fes­sion­al­ly type­set book, news­pa­per, or mag­a­zine. If you agree, then the fact that your col­leagues ha­bit­u­al­ly di­verge from these rules is ir­rel­e­vant. If you don’t agree, then you will prob­a­bly find the rest of this ma­te­r­i­al a bore.

Good ar­gu­ments can be made for both options.

Ex­cept that it’s not a mat­ter of ar­gu­ment. One op­tion has the sup­port of ty­pog­ra­phy au­thor­i­ties and pro­fes­sion­al prac­tice; the oth­er op­tion does not. The is­sue is not am­bigu­ous. Like lan­guage, ty­po­graph­ic con­ven­tions do change. Maybe in forty or fifty years, the habit will be dif­fer­ent. But that’s a top­ic for the tenth edi­tion of this book. For now—one space.

How can I change? I’ve been do­ing it wrong for so long!

OK, no one’s quite said so di­rect­ly. But most ob­jec­tions I’ve heard to this rule (and oth­ers) boil down to in­er­tia. Ex­cus­es like this serve only to im­pede learn­ing and pre­serve bad habits. If you re­al­ly want to learn about ty­pog­ra­phy, set them aside and ap­proach the rest of this book with an open mind.

I will, how­ev­er, en­dorse one ex­cep­tion to this rule:

My boss said I’ll get fired if I don’t use two spaces.

Then let it go. If you’re try­ing to in­still bet­ter ty­pog­ra­phy at the work­place, start with some­thing less provoca­tive. (Per­haps erad­i­cat­ing all caps?) Ad­vo­cates of ty­pog­ra­phy do best when they lead by ex­am­ple, not by decree.