Weight for a 3 mm wetsuit: what to know
Neoprene is full of gas bubbles, so it floats, and it compresses as you descend, so the suit gives less lift at depth than at the surface. A 3 mm suit adds about 2 kg of lift for a typical adult.
Worked example
For an 80 kg diver with an average build, wearing a 3 mm wetsuit and using an aluminum 80 tank in saltwater, the calculator estimates 4.5 kg (10 lb). Your number will differ with your body and gear, so enter your own values above and then do a buoyancy check.
Common questions
How much weight for a 3 mm wetsuit?
Roughly 2 kg more than wearing no suit. Use the calculator, then confirm with a buoyancy check.
Does a hood or vest change it?
Yes. Add about 1 kg for a hooded vest or hood, and re-check.
Do I need less weight in a 3 mm suit than a 5 mm?
Yes. In this model a 3 mm suit adds about 2 kg against about 4 kg for a 5 mm, so you carry roughly 2 kg less for the same diver.
Is 3 mm enough for cold water?
That is a thermal comfort and safety question separate from weighting, and depends on water temperature and dive length. Ask a local dive operator what they recommend.
How do I check weighting after switching suits?
Do a buoyancy check wearing the new suit: float at eye level with an empty BCD, then exhale and sink slowly.
Related calculators
Weight for a 5 mm wetsuitWeight for a 7 mm wetsuitWeight for a drysuitHow much weight do I need?
