Spearfishing Calculators
Free tools for sizing, measuring and comparing speargun equipment. Every calculator states its assumptions and always points back to the manufacturer's own specifications.
Speargun Size Selector
Rule-based reference size ranges by hunting environment, with visibility and experience context.
Open calculatorSpeargun Band Length Calculator
Estimate band length from a measured pull distance, wishbone length and your stretch ratio.
Open calculatorBand Stretch Calculator
Calculate measured stretch factor from relaxed and stretched band lengths.
Open calculatorSpear Shaft Calculator
Geometry-based shaft, overhang and assembled spear length calculations.
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