In a tweet, DuckDuckGo said it had taken seven years for the search engine to reach 10 million private searches in one day.
It took another two years to double that number but only a year to reach 30 million. In contrast, Google handles about 3.5 billion search queries a day but aggressively spies on its users.
A graph issued by DuckDuckGo showed that search queries had begun to spike at certain points when privacy-related events happened.
A further spike, a big one, occurred when there were revelations of privacy issues with Firefox.
As DuckDuckGo is not as aggressive in indexing queries as Google or Bing, its search is less comprehensive.
But as the company says, it does not track users when they use privacy mode or leave it, does not target advertising and stores no personal information.
Chart: courtesy DuckDuckGo