A convertible car seat to stroller device includes a car seat that has a frame, which is rigid. A handle, which is extendable, is coupled to the frame. One of pair of cross supports, each comprising a front member and back member, is pivotally coupled to a bottom of the frame proximate to a left side of the frame. The other of the pair of cross supports is pivotally coupled to the bottom proximate to a right side of the frame. A front axle is rotationally couple to the front members. The front axle is coupled to a pair of front wheels. A back axle is rotationally coupled to the back members. The back axle is coupled to a pair of back wheels. The car seat is couplable to a base, which is couplable to the interior of a vehicle.