That women talk more than men is a common stereotype. A 2007 research study on this question summarized the usual view and its source:

The stereotype of female talkativeness is deeply engrained in Western folklore and often considered a scientific fact. In the first printing of her book, neuropsychiatrist Brizendine reported, “A woman uses about 20,000 words per day while a man uses about 7,000”. These numbers have since circulated throughout television, radio, and print media (e.g., CBS, CNN, National Public Radio, Newsweek, the New York Times, and the Washington Post). Indeed, the 20,000-versus-7000 word estimates appear to have achieved the status of a cultural myth in that comparable differences have been cited in the media for the past 15 years

But is it true? Are females a bunch of Chatty Cathies while males are comparatively laconic?

No.

There is no research that has found that women speak 20,000 words to men’s 7,000. It’s an example of a myth that is oft-repeated with zero grounding in reality. (For other common myths, check out this IFOD: Ten Common Myths That Are Untrue.)

The previously mentioned 2007 research study had 396 volunteers (210 women, 186 men) wear voice recorders over a four-year period and sampled the number of words spoken. The result: “the data suggest that women spoke on average 16,215 (SD = 7301) words and men 15,669 (SD = 8633) words over an assumed period of, on average, 17 waking hours.” The difference didn’t rise to the level of statistical significance.

Another study from 2014 also found that women and men talk about the same amount, but that genders do vary how much they talk based on the setting. The study concluded that “Women were slightly more likely to engage in casual conversation during a lunch hour but much more likely to engage in long conversations during an academic collaboration. However, men were more likely to dominate the conversation when placed in a professional group of six or more people.” Source.