Hi, our 2€/month is indeed a low-entry. About 20% of our users pay voluntarily more to support our mission. As a social enterprise, we do not want to make profits on the subscription, but rather keep it low-cost or support our mission. In the end, it's a mixed calculation, which largely depends on how many searches an average users does (we assume around 80). By the way, Kagi has not built an own index; their model is pretty close to ours.