Visa has revealed that its digital payment service Checkout will now be available across online merchants including Dunkin' Donuts, Pizza Hut, Fandango and Roots. The online payment program, which launched less than a year ago, currently boasts four million customer accounts and is available at more than 125,000 merchants. “With screens and keyboards getting smaller and smaller, checking out online must be incredibly simple and easy,” said Sam Shrauger, Visa’s senior vice president of digital solutions.