sail calculator test page
Sail Area Calculator
Enter your rig dimensions in metres to estimate mainsail, headsail and total upwind sail area. For reference only — actual sail area depends on roach, sail cut and overlap.
Hoist of the mainsail along the mast.
Length of the boom from mast to clew.
From sheer to the top of the forestay.
From mast to forestay attachment at deck.
Defines how far the clew extends aft of the mast.
Multiplier for area added by roach.
Mainsail area —m²
Foretriangle (100%) —m²
Headsail area (150%) —m²
Total upwind sail area —m²
How it's calculated: Mainsail = ½ × P × E × roach factor. Foretriangle (100%) = ½ × I × J. Headsail = foretriangle area × overlap. Total = mainsail + headsail.
