Abstract: An under door seal for interior doors. The under door seal has a U-shaped base unit and a plurality of sealing fins. The base unit mounts to the bottom of a door. The sealing fins are provided to seal a gap between the bottom of the door and the floor to block drafts, light, and sound from passing under the door. The sealing fins have a coiled shape configuration and flexible nature to allow the fins to extend or compress to fill a gap of varied height beneath the door. The flexible nature of the sealing fins also permits the under door seal to seal gaps between multiple floor levels and a single door bottom.