[naishoya]

"77,250words "Unbelievable. Are you actually Stephen Fry in disguise?"

I do concur that a refined collection of incorrect proposed responses which includes selections among terms with semantic proximity, conflated synonyms and plausible morphology could refine the accuracy of evaluations; and if the test was intended to bestow authentic assessments of lexicographical capability this would in all probability become an efficacious approach, but as a simply presentable quiz for folks with sesquipedalian proclivities I was not unduly discomfited by anything moreso than the extraneous clicks leading to and following the display of dichotomous determinations.

[kubb]

Same here (72 750) but it doesn't feel right. I'm not a native speaker and I was able to guess some of them via elimination or cognates.

I'd say I know 10 000 words tops.

[grey-area]

You may know more words than you think, many are shared with French and other Romance languages, particularly the more esoteric ones (see what I did there?). Taking another recherché example: palimpsest - very similar in English, French, Greek.