Common Sense Media says

Clever site emphasizes word comprehension over memorization.

Users say

(out of 4 reviews)
age 8+
Review this title!
Teen, 13 years old Written byslyfox432 September 24, 2013

Fine...

Eh, it's fine, sorta similar to Wikipedia. But if anyone is doing homework and part of it is to do vocabulary, this is not the website for whoever is doing it.
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Educator and Parent Written byEssay Mall September 21, 2013

Interesting

Very cool website. My kids just love it
What other families should know
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Adult Written bySimpson17866 June 13, 2016

Do the same thing on FreeRice instead

FreeRice is a click-to-donate site where this exact same learning experience is used to sell ad-space to support the World Food Programme, donating 10 grains of rice to the third world for every correct answer. Vocabulary.com copies the game exactly, but removes the charity aspect that makes the game productive. Ultimately, the only thing it does is divert potential supporters away from a fantastic humanitarian effort. 0/5 stars. Do this on FreeRice instead.
Adult Written bydashakol April 24, 2016

Website is OK but the app is a total disaster

The website is OK but the app is the most foolish way of wasting time, money and energy I've ever seen in this field. It will infuse new random words in the list of words you are learning. This is very annoying and totally ruining the pleasant experience of recalling the words you've been adding to the learning list till now. The worst thing is that there is no option to turn this stupid feature off! You can't even skip those stupid words. It could be such a perfect match to the website without this. Such a shame this has ruined every thing.