Statisticians Bradley Efron and Ronald Thisted tried to figure out how many words Shakespeare actually knew. This analysis wasn't a trivial task and took pretty long time in 1976. Based upon the results of this analysis Efron and Thisted created a corpus revealing the number of words and frequency of their repetition.
In total, Shakespeare used in his works about 31,500 distinct words (some studies count up to 34,000). Interestingly that some of these words Shakespeare invented himself. A very pragmatic approach, isn't it? But did he employ all the words he knew? Most likely not, because like every human being, he had had active and passive vocabularies. And as we already know, our passive vocabulary is way greater than the active one.
After thorough consideration, the scientists came to the following conclusion: in addition to the number given above Shakespeare knew approximately 35,000 words that he didn't use in his compositions. Thus, they estimated that Shakespeare's real (i.e. passive) vocabulary made up about 65,000 words.
Now let's get back to the point and compare the vocabulary of contemporary people of different ages and educational background with the great classic playwright.
The table below displays the average (very average) figures of vocabulary sizes.
| Education/Age | Vocabulary Size (Base Words) |
| Shakespeare | 34,000* |
| University Graduate | 23,000** |
| Educated Adult (High School) | 15,000 |
| Age 12 | 12,000 |
| Age 5 | 5,000 |
| Age 2 | 300 |
*As mentioned above the actual Shakespeare's vocabulary could have contained over 65,000 words.
**Professional linguists, writers, and journalists may possess much bigger vocabulary.
Take the test and find out your vocabulary size. Do a contest with your friend!