Since the start of the war in Ukraine, use of the language learning app has surged.

Luis von Ahn, CEO and co-founder of Duolingo, said in a statement on Monday that the number of users learning Ukrainian has increased by 485 percent. The majority of the increase is coming from the U.S., but it is global.

The increase in users in Poland is believed to be the result of people welcoming and hosting refugees.

Von Ahn also announced that Duolingo will be donating all of the ad revenue from people studying Ukrainian on the app to charity.

The app will use those partners to give away codes for a free version of the app for refugees and hosts, as well as expand access and provide fee waivers for its English test, which is used for university applications.

Users in Ukraine who were concerned about maintaining their daily progress requested that learning streaks be frozen. Von Ahn said that the app is still free in Russia and Belarus, but that they are disabling monetization in the two countries so that they won't be paying taxes to the Russian government. About 1 percent of its revenue came from Russia.

The statement ends with links to donate to the UN Refugee Agency and the International Rescue Committee, as well as information about organizations that offer translation services.