Interactions using the face, not only enable multi-tasking but also enable us to create hands-free applications. Previous works in HCI used sensors attached directly to the person’s face or inside their mouth. However, a mask, which has now become a norm in our everyday life and is socially acceptable, has rarely been used to explore facial interactions. We designed, “DUMask”, an interface that uses face parts covered by a mask to discretely enable 14 (+1 default) interactions. DUMask uses an infrared camera embedded inside an off-the-shelf face mask to recognize the gestures, and we demonstrate the effectiveness of our interface through in-lab studies. We conducted two user studies evaluating the experience of both the wearer and the onlooker, which validated that the interface is indeed inconspicuous and unobtrusive.