How many words do you really know?
A research-based test that estimates your English vocabulary size in word families — not just words you recognize.
Pick your test
However you start, you’ll walk away knowing something you didn’t before — most people are surprised by their score, in a good way.
Speed Round
A 2-minute game: how many words can you get right? Beat your score and climb the leaderboard.
Vocabulary Estimate
Questions adapt to your level across 25 frequency bands, and you finish with a number: your vocabulary size in word families. Choose how long you want to spend.
No account needed, for the estimate or the Speed Round. Sign in afterwards to save your result and track it over time.
Play with words
Quick games that build vocabulary without feeling like study. Try one — hover to peek inside.
See all 7 games
Ladders, sorting, synonyms, word association and more.
Why your vocabulary size matters
Vocabulary is the single biggest lever on how well you read, write, and follow fast conversation. Knowing your number means knowing exactly what to learn next — and watching it grow is its own kind of fun.
Vocabulary is the ceiling on everything else
It's the single strongest predictor of how well you read, write, and follow fast conversation in English — an unfamiliar word is the most common reason comprehension breaks down, more than grammar ever is.
Word families, not word lists
You're tested on words drawn from all twenty-five 1,000-word frequency bands (1k–25k). The test climbs when you're doing well and backs off when you're not, then extrapolates your total from where it settles.
Watch it actually go up
Once you know your band, you know exactly which 1,000 words to learn next — and retesting later turns "I think I'm improving" into a number you can watch climb.
25 bands of 1,000 word families each, ranked by real-world frequency — the same list the test draws every question from.
What’s a “word family”?
A base word and all the forms built from it. If you know “read”, you very likely also know its family — so we count them together.
How it works
See a word
We show you one word, drawn from a frequency-ranked list of English word families — no sentence, no context clues.
Choose the meaning
Pick the definition that matches the word from four options.
Get your estimate
The test adapts as you answer, climbing toward rarer words when you're doing well, to find your level and extrapolate a total word family count.