A front airbag for a road vehicle; the front airbag having: a stowage compartment formed in a front portion of the dashboard of the road vehicle; a bag normally deflated and folded inside the stowage compartment; and a generator which is housed inside the stowage compartment, is connected to the bag, and inflates the bag in the event of collision; the inflated bag has a longitudinal depth that decreases substantially in a thrust direction perpendicular to a longitudinal axis of the road vehicle.