How long should a sentence be?

Short sentences are easier to understand than long sentences

Add a word to your sentence, and you’ll reduce comprehension. Add another once, reduce it even further. Add another one and reduce it even more.

There’s almost a one-to-one correlation between sentence length and understanding, according to research by the American Press Institute. The research, based on studies of 410 newspapers, correlated the average number of words in a sentence with reader comprehension.

The study found that:

• With average sentences of 8 words or less, readers understood 100% of the story. (Downside: Copy might sound as if it had been ripped from a Dick and Jane book.)
• At 14 words, they understood 90% of the information.
• At 43 words, they understood less than 10%.

And that 107-word sentence your subject-matter expert made you write? It actually subtracts from the sum of human knowledge. After reading that sentence, your readers not only don’t know what they’ve read, they also forget where they parked the car.

That’s a net loss of knowledge — not exactly our goal as communicators.

So how short should sentences be?

Write short sentences like the Times.

Take a tip from the pros at The New York Times, and keep sentences short.

Times sentences average 15 words, according to our analysis of all of the stories in a recent edition of the newspaper. (We skipped the sports pages to avoid skewing the results.)

So aim for an average sentence length of about 15 words, like these from the Times:

Some companies that do approve business-class travel do so only in one direction, however.

Its broadband package is also the home to the sports broadcaster ESPN in Britain.

They added that the plaintiffs’ side lacked actual people to say they were harmed.

Build drama, create rhythm and make points powerfully by sprinkling in some super-short sentences like these, from the Times, which range from 5 to 1 word:

Justice Sonia Sotomayor dissented.

He was 84.

No.

“Times readers are sophisticated and don’t expect ‘Run, Spot, run’ syntax,” writes Philip B. Corbett, who’s in charge of revising the newsroom’s style manual. “But news is read in a hurry, and we should strive for clear, sharp prose that aids rapid comprehension. Long, complex sentences slow readers down and can lead our syntax astray.”

Amen.

How short should a sentence be?

Ask the experts:

A “53-word sentence feels like my junk drawer — too much information crammed into too small a space.”

— Daphne Gray-Grant, publication coach

 “For readable writing that doesn’t tax your readers, vary your sentence length, seek an average in the low 20s, and cut any sentence of 45 words or more.”

— Wayne Schiess, senior lecturer at The David J. Beck Center for Legal Research, Writing, and Appellate Advocacy

 “The 25-word rule isn’t bad as long as you don’t follow it. Don’t count words and stick religiously to the 25-word limit. A long row of sentences all 25 words long can be as dull as a collection of short sentences can be, unless you’re writing for 8-year-olds.”

— Authors of Writing Tips for Word Lovers

 “The ability to write clear, crisp sentences that never go beyond 20 words is a considerable achievement.”

— Joseph M. Williams, the author of Style: Toward Clarity and Grace

 “Writers who demand attention seldom average more than 17 words a sentence.”

— Jack Hart, author of A Writer’s Coach

 “Maximum sentence length: seventeen words. Minimum: one.

“No semicolons. Semicolons indicate relationships that only idiots need defined by punctuation. Besides, they are ugly.

“Make sure each sentence is at least four words longer or shorter than the one before it.”

— Poet Richard Hugo

“There are no absolute rules of good writing — generalizations are instantly riddled with exceptions — but the principle of the 16-word average sentence comes closest. No other single step you can take will show such quick results in clarity and vigor.”

— Jack Cappon, longtime Associated Press editor

 “This sentence has five words. Here are five more words. Five-word sentences are fine. But several together become monotonous.

“Listen to what is happening. The writing is getting boring. The sound of it drones. It’s like a stuck record. The ear demands some variety.

“Now listen. I vary the sentence length, and I create music. Music. The writing sings. It has a pleasant rhythm, a lilt, a harmony.”

— Gary Provost, author of 100 Ways to Improve Your Writing

 “Imagine a clock that starts ticking after the 10th word. With each additional word, the ticking gets louder.

“After the 20th word, the ticking is VERY loud. After the 40th, it’s stadium-crowd loud. After 45, deafening.”

— Tom Silvestri, president of Media General Community Newspapers

What’s your average sentence length? What sentence length do you aim for?