Fun fact: you learn a new word every two days.

By Liz Steelman
Updated August 16, 2016
Riou/Getty Images

In the past, linguists and researchers didn’t have the tools to gauge how many words the average person knows. But, thanks to Twitter, Facebook, and a nation of online quiz-takers, we might finally have an answer. According to a new study from Ghent University in Belgium, the average native English-speaking American will know around 42,000 words by the time they are 20 years old. By 60, they will know around 48,000 words.

The study, published in Frontiers in Psychology, uses data from a viral quiz taken by almost one million people across platforms. According to a release from the sponsoring university, the amount of participants and collected data makes this the largest study of its kind ever attempted.

The test takes about four minutes to complete (you can still take it online in either English or Spanish). First, you are asked personal information—your age, gender, education level, your native language, and how many languages you speak. After completing the demographic profile, a word pops up on the screen. You are then prompted to tap F (NO) on your keyboard if the word is not a word, and J (YES) if it is a word. Each user is shown 70 words. You are also shown 30 letter sequences such as “souaching.” These resemble English spelling constructions, but aren’t actually words. Currently, the test pulls words from a list of more than 62,000 English words. Unlike other viral vocabulary tests, this one doesn’t ask you the meaning of the word. It just tests whether the word shown on the screen is familiar to you.

At the end of the test you can see the percentage of the 62,000 words you are estimated to know. The percentage is based on the number of the existing words you claimed to know minus the number of the non-words you claimed to know. You are also shown the details of words you did not know, non-words that you responded YES to, words you knew, and non-words you responded NO to.

This is just the first major finding from the data. The amount of data and participation means they can mine the information for other interesting findings, like how vocabulary size differs for non-native speakers, or a language’s most prevalent words.

“It also gives us a snapshot of English word knowledge at the beginning of the 21st century. I can imagine future language researchers will be interested in this database to see how English has evolved over 100 years, 1,000 years and maybe even longer,” Marc Brysbaert, study author, said in a statement.

If you’re not too happy with your results, the good news is that you learn a new word every other day, mostly without even having to try. And if you want to learn a whole bunch at once, take a look at, which recently added 300 new words to its inventory.