How Long Would It Take to Read the Whole Dictionary?

There's no one conclusive answer. But that doesn't mean people haven't tried to find one.

While most books live by the standard, front-cover-to-back-cover consumption format, dictionaries (and other reference books) don’t play by the rules. The dictionary is meant to be consumed in bits and pieces, not fully read. One day someone might be reading page 64 of a dictionary, and the next day, boom, they’re on page 697.

But what if the dictionary were to be read like a novel? What if someone did decide to undertake the challenge of reading the thing cover to cover? Exactly how long would that take?

What constitutes “the” dictionary?

Well, getting an exact amount of time is essentially impossible—both because of people’s varied reading speeds and because of the many different options that could be considered “the dictionary.” “Modern readers have access to a wide variety of dictionaries of the English language, and…there is no single authoritative dictionary for the English language,” explains Dr. Adam Crowley, an associate professor of English in Husson University’s College of Science and Humanities.

Dr. Crowley acknowledges that there are some dictionaries that tend to be more popular than others, of course, like the American Heritage Dictionary and the Oxford English Dictionary. But there are lots of varied options for what counts as “the” dictionary, because “there is no agreed-upon central dictionary…for English-speaking people. And there is good reason for this,” he adds, “as the English language is always expanding and changing with the addition of new words and new meanings for old words.” For instance, these 25 new words added to the dictionary in 2019 are only a tiny fraction of the hundreds and hundreds of words added every year. The existence of online dictionaries makes adding new words easier than ever.

So, does that mean it’s impossible to find out how long it would take to read the dictionary? Well, not quite. Unsurprisingly, people have tested this; this is the Internet age, after all, and people have done far weirder things! So there have been a couple of conclusions reached about how long it would take to read dictionary.

Result 1: A full year, in ten-hour chunks

Most mind-bogglingly, in 2008 a man named Ammon Shea read the entire Oxford English Dictionary—as in, the one with 20 different volumes. So this task didn’t just include reading one book—it was reading 20 books, a total of 59 million words and 21,730 pages. And how long did it take him? Well, he didn’t do it in one go. He made it his goal to read it all in one year, spending a maximum of ten hours every day reading. He didn’t calculate his total time, though, as his goal wasn’t to see how long it took him but simply to get it done in a year. And he did! Luckily, even his massive task didn’t include slogging through the longest word in English, which understandably gets left out of dictionaries.

Result 2: Forty-one hours, minimum

But when you think “the dictionary,” you most likely imagine a single, albeit massive, book containing the most relevant words. Don’t worry, that’s been tackled too—sort of. In 2017, Christian Saunders, the founder of English-language teaching platform Canguro English, took on the “reading-the-dictionary” challenge as part of a promotion for World Teachers’ Day. He and a team of more than 30 volunteers live-streamed themselves taking turns reading a 2,000-page version of the Oxford English Dictionary, to raise money to provide English education to refugees. Here, he provides his assessment of the experience as well as some footage of the reading.

But, as you’ll see if you watch the video, there was a catch. Saunders and his colleagues’ task was only to “read every single word in the Oxford Dictionary of English.” They didn’t actually read out the full definitions unless a word really tripped them up or piqued their interest. And just that took a whopping 41 straight hours; we can assume that actually reading out every word of every definition would have taken at least double that time.

So if these two massively varied results reveal anything, it’s that the variations in what can be considered “the dictionary” means there really is no one definitive answer. But the good news is that if you’re going to tackle this task, you’re well within your rights to choose a shorter version of the dictionary. Since there’s no single, universally accepted “dictionary,” no one can tell you it doesn’t count. Next, find out some more fun facts you never knew about dictionaries.

Meghan Jones
Meghan Jones is a word nerd who has been writing for RD.com since 2017. You can find her byline on pieces about grammar, fun facts, the meanings of various head-scratching words and phrases, and more. Meghan graduated from Marist College with a Bachelor of Arts in English in 2017; her creative nonfiction piece “Anticipation” was published in the Spring 2017 issue of Angles literary magazine.