“We want to bring transparency to an otherwise unregulated market,” says Jodi Manning, who oversees travel partnerships as vice president and director of marketing at Cool Effect, a nonprofit crowdfunding platform for vetted carbon projects. Three months ago, Manning overhauled the company’s two-year-old travel calculator, allowing consumers to clearly see—in just three clicks—how much it would cost to offset a flight, and where that money would go. “We need to make sure our buyer understands how much is going to the projects and how much is going to the fee.” The new features help travelers see that offsetting flights can be both affordable and effective—just $10 for a medium-haul ticket—which has multiplied individual donations sevenfold. (It also helps that Cool Effect has excellent documentation on each project it funds, whether it’s building wind turbines in Costa Rica or American Indian-run methane-capture initiatives in Colorado.)