Great question! Our Duo 6 Quart mode is a 7-in-1 multicooker that has 13 preset smart programs. The Viva 6 Quart model is a 9-in-1 multicooker that has 15 preset smart programs. The Viva has all the same functions as the Duo, minus the Steam function, plus a few extra such as Cake, Egg, Sous Vide, and Sterilize.
The Viva has a new EasySeal Lid that automatically sets to seal for pressure cooking, whereas the Duo lid is set manually. Both models come with the same accessories.
We hope that helps! Happy Cooking!