The Wing Chords Calculator turns your fixed wing parameters — span, surface, and taper ratio — into draw-ready root, tip, and mean chords. It introduces no new design decisions; it solves the geometry once the decisions are made.
Enter wingspan, wing surface, and taper ratio to get root chord, tip chord, and MAC.
Why this comes after the ratios
By this point in the method, the wing’s behavior is already defined: mission, surface, aspect ratio, taper, and sweep are set. What’s still missing is dimension. Ratios describe distribution, not measurements, so root chord and tip chord have to be solved from the linked relationship between span, surface, and taper. That’s mechanical math, not a design decision, which is exactly what this tool exists to handle.
How it’s calculated
Root and tip chord come from the trapezoidal wing area formula, solved for root chord given span, surface, and taper ratio. Tip chord follows directly as taper ratio × root chord. MAC (mean aerodynamic chord) is then derived from root chord and taper ratio, it’s the single reference length the rest of the airplane’s longitudinal geometry will be measured against.
What to do with the result
These three numbers are what you’ll actually draw. Root and tip chord define the wing’s planform outline; MAC becomes the reference for positioning the wing on the fuselage and setting CG limits later in the method.
Next step
The wing is now fully dimensioned. Continue to Airfoils — the next step in the method.
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