flight mechanics, the taper ratio (TR) is a parameter used to describe the shape of an aircraft wing. The taper ratio represents the ratio of the wing’s root chord (the chord at the wing’s root or base) to the wing’s tip chord (the chord at the wing’s tip).
The formula to calculate the taper ratio is as follows:
TR are  λe = Root Chord / Tip Chord
Where: TR = Taper Ratio Root Chord = Chord length at the wing’s root (base) Tip Chord = Chord length at the wing’s tip