The flexible door seal device provides for sealing against air leaks around a door and doorway without interfering with door opening and closing. The flexible device is easily installed and removed without need of any tools. Also, the device can be rolled or folded into a compact size for transport and storage as needed. The device is self-retained until removed from a door. Retention is accomplished by way of the pockets disposed at each corner. Ideally, the device may be seamless. The device provides a positive seal by way of the insert and the inner flap and outer flap that overlap any space between a door and a jamb. The outer flap is sufficient to overlap drywall, trim, and other door surrounds.