The idea is that you, as a user of the search engine, plant trees while you search the web.
Ecosia uses the profit they make from search ads to plant trees where they are needed most. As of this writing, Ecosia has planted more than 117 million trees. Yes, they publish their financial reports.
In terms of privacy, Ecosia does not create personal profiles of you based on your search history. They anonymize all searches within one week. In addition, they do not sell data to advertisers.
Here’s a review of the company.
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