how many English words do you know? ..." with this test you get a valid estimate of your English vocabulary size"

The Centre of Reading Research at Ghent University in Belgium is very interested in seeing how much and what type of vocabulary we use.

It regularly carries out research - which catches the public eye.

And it also offers the same test it's used in its research for the rest of us to try.

This is from 2014:

Center for Reading Research study finds different vocabulary words are known to only to men or women.

Mach and mascarpone: testing how vocabulary is gendered | Written language | The Guardian

Gender and Vocabulary Analysis

This is from 2016:

Most adults know more than 42,000 words -- ScienceDaily

How Big Is Your Vocabulary? This Online Test Can Find Out | Digital Trends

And this is from 2017:

No more queueing at the ladies' room: How transgender-friendliness may help in battling female-unfriendly toilet culture -- ScienceDaily

And this is from this year, as reported by the E L Gazette:

A new vocabulary list reflects how learners acquire additional words

The order of words acquired by non-native learners is usually assumed to reflect word frequency in the English language generally, but when Belgian researchers tested word recognition directly and compiled lists of word families reflecting what students actually know, their lists suggested other strong influences on which words are learned and in what order...

The Belgian study took a very different, bottom-up approach, testing language learners directly to find out which words they actually know.

An internet test was made freely available (see below), with each testing round comprising 70 random, real English words and 30 random, made-up but plausible words. The participants answered yes/no, indicating recognition of the word, while the inclusion of the nonsense words weeded out those who claimed to recognise words falsely.

Measuring language learning success | E L Gazette

And here's their test:

How many English words do you know? With this test you get a valid estimate of your English vocabulary size within 4 minutes and you help scientific research.

Vocabulary test

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