Some people prefer Google when exploring the Web. Some like Yahoo or Bing. But now more than 2.5 million people a month are using Ecosia, because every time they click “Search” they help plant a tree.

Ecosia donates an impressive 80 percent of its income, after expenses, to programs that sows trees in Africa. The money, up to $75,000 a month (most of it from ads), is responsible for four new trees every minute, according to Ecosia spokesperson Jacey Bingler. That’s up from one tree a minute just two years ago, when I first wrote about the site, which went live in 2009.

The group, based in Germany, had been funding a tree program in Brazil but last October it began financing WeForest’s reforestation project in Burkina Faso, West Africa. It is part of a larger effort to spread greenery across dry regions of Africa. Bingler noted by email that the project has a larger purpose, too. “It's about reviving drought-ravaged landscapes, nurturing, educating and empowering people, slowing the spread of disease and even reducing the likelihood of extremism and violent conflict.”

Ecosia’s goal is to sprout 1 billion trees by 2020. Originally it hoped to reach that level by this year, but planting costs were high and users did not quickly flock to the search engine. That is all picking up steam today. “We celebrated our first million trees in November 2014, the second million already in May 2015,” Bingler noted. And the cost in Burkina Faso works out to about 30 cents a tree, instead of the dollar being spent before.

Bingler noted that the search engine continues to improve; searches are now 34 percent faster than they were last year. It is powered primarily by Bing and is enhanced with Ecosia’s own algorithms and technologies. Users can also click a “Google” button, which gives that engine’s results for the same inquiry. Bingler added that Ecosia is an important alternative to the big players “because it empowers users to do good without spending a penny. Highly abstract everyday tasks, like searching the Web, can lead to something as tangible as a new tree.”