Certain aspects and embodiments of the present invention provide an airbag having a vent that can adaptively release gas from the airbag upon impact with an occupant. The vent may include a membrane and/or diaphragm that can control the amount of gas released from the airbag based on the pressure in the airbag. During a collision, the airbag can be filled with gas and absorb the energy from an occupant causing the pressure in the airbag to increase. The adaptive vent can release gas from the airbag by opening when the occupant impacts the airbag. In some embodiments, the size of the vents changes depending on the pressure existing in the airbag.