Abstract: An automobile window ventilator in which a fan is mounted to the window via panels. The fan causes the forced exchange of hot interior air with cooler ambient air, which fan is used especially in the parked state of the vehicle. The fan is powered from the d.c. voltage source of the vehicle, and is readily convertible to a swiveling cooling fan for cooling persons in the interior of the vehicle via an adapting structure. The panels snugly receive the window pane therebetween, which panels are held in place in the channels of the window frame via L-shaped clips. The control of the fan is automatic via a thermal switch sensing the interior temperature of the vehicle. The upper panel may be used for mounting a conventional static vent screen. A closure lid for closing off or exposing the dynamic vent is provided, which is adjustably positionable from the interior of the vehicle. An anti-tampering screen mesh denies unwanted access to the interior of the vehicle via the window mounting the dynamic vent.