3-Minute Test
Free Vocabulary Test
Forty words, eight of them fake. Mark the ones you know and get an estimate of your vocabulary size, plus the difficulty tier where your knowledge stops. Free, about 3 minutes, no signup.
Released August 8, 2026 · Updated August 8, 2026
This free vocabulary test estimates how many English words you know using a yes/no recognition task with hidden fake words that correct for overconfidence. You review 40 words across four difficulty tiers, mark the ones you recognize, and get an estimated vocabulary size with a band-level breakdown. The benchmark: the average adult native speaker of American English knows about 42,000 lemmas, per Brysbaert et al. (2016).
1Take the test
3 minutes, 40 questions. No account, no email, nothing to unlock.
2Read your result
Instant scores with honest interpretation bands, plus the one area where you scored weakest.
3Fix the weak spot
NerdSip generates a fact-checked 5-minute course on exactly that area. First lesson is free.
What a Vocabulary Test Actually Measures
Vocabulary tests come in two flavors. Multiple-choice quizzes check depth: whether you can pick the right meaning of a word from four options. Recognition tests check breadth: how many words you know at all. This test measures breadth, because breadth is what the famous vocabulary size numbers describe.
The format is the yes/no recognition task, a standard tool in psycholinguistics since Meara and Buxton introduced it in 1987. You see a word and say whether you know it. No definitions, no trick options, no time pressure. It sounds too simple to work, and on its own it would be. That is why eight of the forty entries are fake, a correction explained below.
The words themselves are sampled across four difficulty bands, from workhorses like reluctant to rarities like apricity, the warmth of the sun in winter. Where your recognition falls off tells the engine which tier of the dictionary you own.
The benchmark comes from one of the largest word studies ever run. Brysbaert, Stevens, Mandera and Keuleers analyzed recognition data from more than 220,000 people and published the results in Frontiers in Psychology in 2016. Their headline finding: the average 20-year-old native English speaker knows about 42,000 lemmas, the base forms of words. That number anchors your estimate.
Why Eight of the Forty Words Are Fake
Ask people to rate their own vocabulary and almost everyone lands on above average. Yes/no tests share the weakness: saying "I know it" costs nothing, so scores drift upward with confidence rather than knowledge. Researchers solved this decades ago with a simple trap. Mix in pseudowords, invented strings like brelliant or manthrophy that follow English spelling rules, sound perfectly plausible, and mean nothing.
The logic is called signal detection, the same math behind radar screens and medical screening. Every real word you recognize is a hit. Every fake word you claim is a false alarm, and each false alarm suggests some of your hits were bluffs too. The engine subtracts a penalty scaled to your false-alarm rate, so a careful reader who honestly marks 25 words can outscore a confident one who marks 35 and falls for three fakes.
Serious research instruments work exactly this way. LexTALE, a widely used lexical test published by Lemhöfer and Broersma in 2012, is 40 items in the same format for the same reason. Most online vocabulary quizzes skip the correction, because uncorrected scores are flattering and flattering scores get shared. We would rather hand you a smaller number you can believe. If your result here lands lower than on another site, this is why, and it is a feature.
How the Scoring Works
Your score is hits minus a false-alarm penalty. Every real word you mark is a hit; every pseudoword you mark is a false alarm that subtracts more than a hit is worth, because it casts doubt on all your other claims. The corrected total is normalized to a 0 to 100 score and mapped against the distribution in the Brysbaert dataset to produce an estimated vocabulary size in lemmas.
The band breakdown is where the useful information lives:
| Band | Tier | Example |
|---|
| 1 | Everyday | reluctant |
| 2 | Educated | laconic |
| 3 | Advanced | perspicacious |
| 4 | Rare | apricity |
Most people's recognition falls off a cliff at one specific band, and that cliff is your reading frontier: the tier where new words are waiting for you.
Two honest caveats. Forty items cannot count forty thousand words; the estimate projects from a sample and carries a real margin of error, so treat it as a range, not a census. And this is a self-report of recognition, useful for self-knowledge and entirely unsuitable as a clinical, educational, or hiring assessment.
How to Grow the Number
Vocabulary is one of the few mental measures that improves for life. In the Brysbaert data, the average person adds about 6,000 lemmas between ages 20 and 60, one new word every two days, and nearly all of it comes from reading. The growth is automatic but slow. Three habits compound it.
- Read slightly above your level. Comprehensible struggle is the sweet spot: a page with two or three unfamiliar words gives you context to decode them without drowning you. What you do next matters more, and our guide on how to remember everything you read covers turning encounters into retention.
- Learn roots, not lists. English is a compression scheme. More than half its vocabulary is built from Latin and Greek parts, so one root unlocks dozens of words. Anyone who knows bene and dict can decode benediction on sight. This is the leverage play, and it is why the etymology course we generate for low scorers starts there.
- Use words out loud. A word you recognize but never deploy is only half owned. Working new words into real conversation cements them, and there is a craft to doing it without sounding like a thesaurus, covered in how to sound smarter in conversations.
For the wider habit of turning curiosity into a system, see how to become more knowledgeable.
How Many Words Does the Average Person Know?
The best answer comes from the 2016 Frontiers in Psychology study by Marc Brysbaert and colleagues, built on recognition data from more than 220,000 test-takers. Their estimate: the average 20-year-old native English speaker knows about 42,000 lemmas, drawn from roughly 11,100 word families, plus around 4,200 multiword expressions like bite the bullet. By age 60 the average climbs to about 48,000.
The spread is wide. At 20, the lowest 5 percent of native speakers know around 27,000 lemmas and the highest 5 percent around 52,000, a gap of two reading lifetimes.
You may have seen smaller numbers, 20,000 to 35,000, quoted by other vocabulary size tests online. The gap is definitional, not contradictory. Counting lemmas (run, running and ran count once) gives different totals than counting word families or dictionary entries, and a vocabulary quiz that requires knowing a word's meaning lands lower than one measuring recognition. When you test your vocabulary, the honest question is not just how many words you know but by what definition of both know and word.
That slipperiness is exactly what makes average vocabulary size a great dinner-party topic, and if you enjoy those, we keep a whole shelf of facts that make you sound smart.
The instrument behind this test
Yes/No Vocabulary Recognition Task with Pseudoword Correction. Original word list; format and false-alarm scoring modeled on the yes/no methodology of Meara and Buxton and of LexTALE, with size norms from Brysbaert et al. (2016). A self-report estimate, not a clinical or educational assessment. Reference: Meara, P., & Buxton, B. (1987). An alternative to multiple choice vocabulary tests. Language Testing, 4(2), 142-154; scoring per Lemhöfer, K., & Broersma, M. (2012). Introducing LexTALE. Behavior Research Methods, 44(2), 325-343; norms from Brysbaert, M., Stevens, M., Mandera, P., & Keuleers, E. (2016). Frontiers in Psychology, 7:1116. Score norms: Brysbaert, M., Stevens, M., Mandera, P., & Keuleers, E. (2016). How Many Words Do We Know? Frontiers in Psychology, 7:1116.
Sources and further reading
Released August 8, 2026 · Last updated August 8, 2026
Frequently asked questions
How many words does the average person know?
About 42,000. Brysbaert and colleagues, analyzing recognition data from more than 220,000 people in a 2016 Frontiers in Psychology study, found the average 20-year-old native English speaker knows roughly 42,000 lemmas, the dictionary base forms of words. The range runs from about 27,000 for the lowest 5 percent to 52,000 for the highest, and the average grows to about 48,000 by age 60.
How can I test my vocabulary size?
Take a recognition test that includes fake words. You mark which words you know from a list sampled across difficulty levels, and pseudowords catch overclaiming so the estimate stays honest. This page runs exactly that format: 40 items, about 3 minutes, free, no signup. Multiple-choice quizzes measure how precisely you know words, but recognition with a guessing correction is the standard method for estimating total size.
What is a pseudoword?
A pseudoword is an invented string of letters that obeys English spelling and sound rules but has no meaning, like brelliant or cordurance. Because it looks and sounds like it could be real, it makes a perfect trap for overconfidence. Vocabulary researchers mix pseudowords into recognition tests: anyone claiming to know them is guessing, and their real-word claims get discounted accordingly.
What is a good vocabulary size?
For adult native English speakers, anything near 42,000 lemmas is typical, and avid readers reach 50,000 or more. Context matters: an eight-year-old with a fraction of that is right on track, and a fluent non-native speaker can thrive on far fewer. Size also matters less than reach; knowing the precise word for a thing beats knowing ten vague ones.
How accurate is this vocabulary test?
It is an honest estimate, not a census. Forty items cannot count 40,000 words; the test samples four difficulty bands and projects from where your recognition drops off, with fake words correcting for lucky guessing. Expect your true size to sit in a range around the estimate. That still beats most online vocabulary quizzes, which skip the guessing correction and inflate scores.
Why does the test include fake words?
Because saying "I know it" costs nothing. Without a check, confident test-takers outscore knowledgeable ones. The eight pseudowords act as tripwires: every fake word you claim signals that some of your real-word claims were guesses too, and your score is corrected downward. This is the same signal-detection logic used in established research instruments like LexTALE.
Can adults still improve their vocabulary?
Yes, and measurably. The Brysbaert data shows the average person adds about 6,000 lemmas between ages 20 and 60, roughly one new word every two days, mostly through reading. Deliberate habits speed this up: reading slightly above your comfort level, looking up words you almost know, and learning Latin and Greek roots so unfamiliar words decode themselves.
Is this vocabulary test free?
Yes. Free, no signup, no email gate, and your results appear immediately, including the band breakdown. NerdSip makes an app that generates fact-checked 5-minute courses on any topic; this test is the same craft applied to measurement. If your result reveals a weak spot, we will offer a course built for exactly that, but the test itself asks nothing of you.
