In aerospace engineering, payload fraction is a common term used to characterize the efficiency of a particular design. Payload fraction is calculated by dividing the weight of the payload by the takeoff weight of aircraft. For spacecraft the payload fraction is often less than 1%,
The Falcon Heavy has a liftoff weight of 1421 metric tons and can put 63.8 tons into low earth orbit (4.49% payload to orbit)
The Delta IV heavy has liftoff weight of 733 metric tons (808 tons) and can place 28.8 metric tons (3.9% of payload) into low earth orbit.