Scuba Weight Calculator

About this calculator

A diver in a wetsuit is naturally buoyant — the neoprene traps air that floats, and salt water is denser (and more buoyant) than fresh water — so extra lead is worn to descend and hold a controlled, neutral hover at depth. A common starting estimate uses roughly 6–10% of body weight as a base, adds weight for wetsuit thickness (thicker neoprene traps more air and needs more lead), and subtracts a bit for fresh water, which is less buoyant than salt water.

Too little weight leaves a diver unable to descend or hold a safety stop; too much wastes air fighting negative buoyancy and strains the back. Scuba instructors, dive shops and divers themselves use a starting estimate like this before fine-tuning with an actual buoyancy check at the surface, since body composition, exposure suit, tank material and gear all shift the ideal number.