⚓ Scuba Weight Planner
Customize lead weight requirements for salt or fresh water using common suit thicknesses and tank types.
Lead Weight Needed (empty tank)
13.8 kg
30.4 lb
With Full Tank
9.3 kg
20.5 lb
How to Use This Calculator
Enter body weight
Used to approximate natural buoyancy.
Select water type
Salt water requires more lead than fresh water.
Choose exposure suit
Thicker suits add buoyancy; drysuits require more weight.
Pick tank type
Aluminum and steel tanks have different buoyancy characteristics.
Review recommended weight
Use results as a baseline; conduct buoyancy checks for precision.
Formula
Total Lead = Suit + Water + Body + Tank
Suit: estimated buoyancy (lbs) • Water: salt adds ~2 lb advantage • Body: +1% body weight • Tank: buoyancy difference between full/empty.
These estimates align with common dive training tables. Adjust based on personal buoyancy tests, gear configuration, and water salinity.
Buoyancy Tips
Proper weighting ensures safe ascents, efficient air use, and stable safety stops. Overweighting increases exertion; underweighting risks uncontrolled ascents.
Best Practices
- Perform weight checks at the end of dives with ~500 psi remaining and empty BC.
- Distribute weights evenly (trim pockets, tank bands) for horizontal trim.
- Adjust weights when switching exposure suits, tanks, or diving environments.
Frequently Asked Questions
How do I conduct a proper weight check?
With 500 psi left, empty your BC at eye level in freshwater (or with 2–3 lb extra in salt water). You should float at eye level and sink slowly when exhaling.
Why include tank buoyancy?
Tanks become more buoyant as air is used. Accounting for empty tank buoyancy prevents positive ascents near the end of the dive.
Do aluminum and steel cylinders feel different?
Yes. Steel cylinders remain negative; aluminum becomes positive when empty and often requires more lead or ballast.
How often should I re-check weights?
Whenever you change gear (suit, tank), dive location (fresh vs salt), or after a long break from diving.
Can I estimate bullet weights (belt vs integrated)?
Use the total lead estimate for belts or integrated systems. Distribute weight for comfortable trim and easy ditching if needed.