A vocabulary estimator
Every Word You Know
vo·cab·u·lar·y /vəˈkabələri/ · noun the body of words a person knows.
You use a few thousand words a week and recognise many times more. Mark the ones you know below — including, if you spot them, the ones that aren't real — and find out roughly how many live in your head.
Mark the words you know
words you'd recognise
A few you didn't mark
About This Tool
There is a strange gap between the words you use and the words you know. A person might write with three or four thousand words in a normal week, yet recognise ten times that many the instant they see them. This tool tries to measure the second, larger number.
It works the way linguists estimate vocabulary size: instead of testing everything, it samples. You are shown words spread evenly from the most everyday to the genuinely obscure, and the tool watches where your recognition falls off. That drop-off point, extrapolated across the whole language, is your estimate.
The Fake Words
Some of the words in the list do not exist. They look plausible — they follow the rules of English spelling — but they were invented for this test. They are not there to trick you for sport. They are controls.
If you mark a handful of real words you half-recognise, you will probably mark a fake or two as well, and that tells the tool you are rounding up. It then corrects your entire estimate downward in proportion. It is the single feature that separates an honest vocabulary estimate from a flattering one, and every serious version of this test uses it.
Why This Exists
Because "how many words do you know" is one of those questions everyone has wondered and almost nobody can answer, and the honest answer is more interesting than people expect. The number is large — tens of thousands — and most of it is passive, a vast quiet reserve you never actively use but would miss the moment it was gone.
Seeing the figure also changes how you read. Once you know that your recognition thins out somewhere past the common few thousand, every rare word you meet afterwards feels less like decoration and more like a small addition to a collection.
Frequently Asked Questions
How does Every Word You Know estimate my vocabulary?
It shows you a sample of words drawn evenly from six frequency bands, from everyday words to obscure ones. For each band it measures the share you recognise, multiplies that share by the real number of English words in that band, and adds the bands together. Because knowledge falls off sharply as words get rarer, sampling by band gives a far better estimate than simply scaling one overall percentage.
Why are there fake words in the list?
Some of the words shown are invented and do not exist in English. They are controls. If you mark fake words as known, the tool knows you are over-claiming, and it corrects your whole estimate downward using the false-alarm rate. This is the same method proper yes-or-no vocabulary tests use to keep people honest.
How accurate is the number?
It is a statistical estimate, not a precise count, and it will move by a few thousand each time you play because the sample is random. It counts word forms you would recognise rather than strict dictionary head-words, so treat it as a good ballpark rather than an exact figure.
How many words does a typical person know?
Most adult native English speakers recognise somewhere between 20,000 and 35,000 words, with heavy readers higher and younger or non-native speakers often lower. Recognising a word is easier than being able to use it, so recognition estimates like this one tend to sit at the higher end.
Where do the words come from?
The words are drawn from a standard English frequency list and filtered against a large dictionary so that every real word shown is genuinely a word. They are ranked by how common they are, which is what lets the tool sort them into frequency bands.
Is anything saved or uploaded?
No. Everything runs in your browser. Nothing you click is uploaded or stored anywhere, and nothing is shared unless you choose to share your result yourself.
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