Using new surveys on more than 40 000 respondents in twenty countries that account for 72% of global CO2 emissions, we study the understanding of and attitudes toward climate change and climate policies. We show that, across countries, support for climate policies hinges on three key factors: the perceived effectiveness of the policies in reducing emissions, their perceived distributional impacts on lower-income households (inequality concerns), and their own household’s gains and losses. We also show that information that specifically addresses these key concerns can substantially increase the support for climate policies in many countries. Explaining how policies work and who can benefit from them is critical to foster policy support. Simply making people more worried about climate change is not an effective strategy to foster policy support. Furthermore, we identify several socioeconomic and lifestyle factors – most notably education, political leanings, car usage, and availability of public transportation – that are significantly correlated with both policy views and overall reasoning and beliefs about climate policies. Yet, it is difficult to predict beliefs or policy views based on these characteristics only.