Freediving Weight Calculator
Estimate how much weight you need for your freediving setup. Remember: this is a starting point only.
Your Details
Estimated Weight
Starting point for neutral buoyancy at ~10m depth
This is an estimate only
- •Use small increments (0.5-1kg) to fine-tune in the water
- •Every body is different - test and adjust
- •Wetsuit compression at depth affects buoyancy
- •Always be positively buoyant in the top 10m for safety
How to Properly Test Your Weighting
A calculator gives you a starting point, but the only way to find your correct weight is to test in the water. Your buoyancy is affected by lung volume, relaxation, and even your mental state. Here's how to dial it in:
Pool / Dynamic Training
For dynamic apnea, you want to be neutrally buoyant in mid-water - not floating to the surface, not sinking to the bottom.
The glide test:
- Take a full breath and push off the wall
- Do 1-2 kicks, then glide with arms by your sides
- Wait patiently until you stop moving
- Observe: do you float up or sink down?
Adjust in 0.5kg increments until you glide horizontally without rising or sinking.
Depth / Open Water Training
For depth diving, aim to be neutrally buoyant at around 10m (33ft). This ensures you're positively buoyant in the danger zone (top 10m) where blackouts are most risky.
The 10-meter test:
- Descend to exactly 10m on a line
- Stop completely - remove all momentum
- Let go of the line and stay motionless for 10 seconds
- Observe: do you float up, sink, or stay still?
If you sink, remove weight. If you float, add weight. Neutral = perfect.
Quick Surface Check
Float vertically with your fins pointing down and arms at your sides. After a passive exhale (not forced), the water level should be between your chin and lower lip. If water is above your mouth, you have too much weight. If it doesn't reach your chin, add weight.
Safety First
Never be overweighted. Being too heavy makes it hard to breathe up at the surface, shortens your breath-hold, and critically - if you blackout near the surface, you will sink instead of float. When in doubt, use less weight. You must be positively buoyant in the top 10 meters.