Freediving Weight Belt Setup Guide: Calculate, Distribute, Release

Proper weighting is one of the most overlooked yet critical aspects of freediving. Get it wrong, and you'll exhaust yourself fighting buoyancy on descent, waste energy ascending, or worse — struggle to return to the surface in an emergency. This guide covers how to calculate your ideal weight, distribute it correctly, and choose the right belt system.

Why Weighting Matters in Freediving

Unlike scuba diving (where you want neutral buoyancy at depth with a full tank), freediving weighting is about achieving neutral buoyancy at a specific target depth — typically 10-15 metres for recreational diving.

Here's why:

• 0-10m (Positive buoyancy): You're fighting upward — requires active finning to descend

• 10-15m (Neutral buoyancy): You neither sink nor float — effortless gliding

• 15m+ (Negative buoyancy): You sink naturally — enter freefall, minimal energy expenditure

If you're overweighted, you sink too early and fight buoyancy on the way up. If you're underweighted, you exhaust yourself finning down and never reach freefall. The goal is to find the sweet spot where you transition from positive to negative buoyancy at your target depth.

Understanding pressure and buoyancy changes with depth is fundamental. Read our guide to Boyle's Law and pressure.

Factors That Affect Your Weighting

Your ideal weight depends on several variables:

1. Wetsuit Thickness

Neoprene is buoyant. The thicker your wetsuit, the more weight you need:

• No wetsuit or rash guard: 0-1 kg

• 1-2mm wetsuit: 1-2 kg

• 3mm wetsuit: 2-4 kg

• 5mm wetsuit: 4-6 kg

• 7mm+ wetsuit: 6-8+ kg

These are rough starting points. Open-cell wetsuits compress slightly less than lined suits, so they require marginally less weight. Read our wetsuit guide for more on neoprene types.

2. Body Composition

Muscle is denser than fat. Lean, muscular divers generally need more weight than divers with higher body fat. Women typically need 1-2 kg less than men of similar size due to slightly higher body fat percentage.

3. Lung Volume

Larger lungs mean more buoyancy. Divers with above-average lung capacity (6+ liters) may need 1-2 kg more weight than average.

4. Saltwater vs Freshwater

Saltwater is denser and more buoyant. You need approximately 2-3 kg more weight in saltwater compared to freshwater.

5. Target Depth

Neoprene compresses at depth, losing buoyancy. If you weight for neutral at 10m but plan to dive to 40m, you'll be quite negative by the time you reach depth. Advanced divers who regularly go deep (30m+) often use slightly less weight to avoid being overly negative on ascent.

How to Calculate Your Ideal Weight

The Float Test Method

This is the gold standard for determining correct weighting:

1. Wear all your freediving gear (wetsuit, mask, fins)

2. Enter the water with an estimated starting weight

3. Take a normal breath (not maximum, not empty — just a relaxed full breath)

4. Relax completely and float vertically in the water

5. The waterline should be at eye level when you have a normal breath

Adjust weight:

• If you float with water below your eyes → add 0.5-1 kg

• If you sink below eye level → remove 0.5-1 kg

• Repeat until waterline sits at eye level with a normal breath

This method produces neutral buoyancy at approximately 10 metres — ideal for most recreational freediving.

The Descent Test Method

A more precise (but advanced) method:

1. Perform the float test to get close

2. Do a dive to 10-15 metres

3. At your target depth, exhale fully and observe what happens

4. You should hang motionless (neutral) or very slowly sink

5. If you pop up after exhaling → add 0.5-1 kg

6. If you sink quickly → remove 0.5 kg

This fine-tunes for your exact diving style and depth range.

Rubber Belt vs Webbing Belt

Rubber Weight Belt

• Pros: Stretches and contracts with your wetsuit and body as you descend/ascend, maintaining consistent tension; doesn't slip; preferred by 90% of freedivers

• Cons: Degrades over time (UV and saltwater); more expensive than webbing; can be harder to thread weights onto

Rubber belts are the standard for freediving. The stretch compensates for wetsuit compression at depth, preventing the belt from loosening and sliding.

Webbing (Nylon) Weight Belt

• Pros: Cheap, durable, easy to find

• Cons: Doesn't stretch — can become loose at depth as wetsuit compresses; requires frequent adjustment; can slip during ascent

Webbing belts work for shallow diving (<15m) or when not wearing a wetsuit, but most serious freedivers prefer rubber.

Quick-Release Buckle: Critical Safety Feature

Your weight belt must have a quick-release buckle that can be opened with one hand in a single motion. In an emergency — failed equalization, blackout, leg cramp, entanglement — you need to be able to ditch your weights instantly.

The Marseillaise buckle (cam buckle) is the most common quick-release system for freediving. Test your buckle on land before every session:

• Can you open it with one hand while wearing a glove?

• Does it release instantly without jamming?

• Can you open it while looking away (simulating disorientation)?

If the answer to any of these is no, replace your buckle immediately. Safety equipment that doesn't work when you need it is worse than useless. Read our guide to freediving safety protocols.

Weight Distribution: Where to Place Your Weights

Most freedivers wear a single belt around the waist, but weight distribution along that belt matters:

Standard Distribution (Recreational)

• Place weights evenly distributed around your hips

• Slightly more weight on your sides and back, less on your belly (comfort)

• The buckle sits on your right hip (right-hand release)

Advanced Distribution (Streamlining)

• Some competitive divers place all weight on their lower back (centerline) for better streamlining

• Neck weights (small 0.5-1kg weights on a separate lanyard) can improve head-down positioning — used by elite depth divers but not recommended for beginners

For depths beyond 30m, proper streamlining becomes critical. Read about depth progression and technique.

Types of Weights

Lead Weights

• Pros: Dense (small size for given weight), cheap, widely available

• Cons: Toxic if paint flakes off (use coated weights), can corrode

• Sizes: Typically sold in 0.5kg, 1kg, and 2kg increments with a slot to thread onto belt

Lead is the standard. Ensure your weights are coated or painted to prevent lead exposure.

Rubber-Coated Weights

• Pros: Quiet (no clanking), protected from corrosion, more comfortable on hips

• Cons: Slightly more expensive; coating can tear over time

These are worth the premium if you dive frequently. The reduced noise is appreciated during static apnea and competition.

Soft Weights (Shot Pouches)

• Pros: Conform to body shape, comfortable, easy to adjust

• Cons: Bulkier than solid weights; less common

Soft weights are less popular in freediving but work well for shallow training and travel (easier to pack than solid lead).

Common Weighting Mistakes

1. Too Much Weight

The most common error. Overweighting makes ascent exhausting, wastes energy, and in an emergency makes it harder to reach the surface. Err on the side of slightly underweighted if unsure.

2. Using Scuba Weighting

Scuba weighting aims for neutral buoyancy at depth with a full tank. This is typically 4-6 kg more than freediving weight. Never use your scuba weighting for freediving.

3. Not Adjusting for Conditions

If you switch from a 3mm to a 5mm wetsuit, or from freshwater to saltwater, your weight needs change. Always recheck your weighting when conditions change.

4. Ignoring Wetsuit Compression Over Time

As your wetsuit ages and compresses permanently (especially after many deep dives), it loses buoyancy. You'll need slightly less weight after 6-12 months of regular use. Retest periodically.

Weighting for Different Disciplines

Constant Weight (CWT) — Depth Diving

• Neutral at 10-15m

• Allows freefall to begin around 15-20m

• Typical range: 2-6 kg depending on wetsuit

Static Apnea (STA) — Pool

• Neutral or slightly positive at surface

• Just enough weight to stay submerged without effort

• Typical range: 1-3 kg, sometimes zero if no wetsuit

Dynamic Apnea (DYN) — Horizontal Pool Swimming

• Neutral at surface or 1-2m depth

• Minimal weight for streamlining

• Typical range: 0-2 kg

Different disciplines have different needs. Read our guide to freediving disciplines.

Safety Considerations

Safety Reminder: Your weight belt is safety equipment. Practice ditching it on land and in shallow water until it's automatic. In an emergency, dropping your weights can be the difference between a safe ascent and tragedy.

• Train with your buddy to ditch weights quickly

• Check your quick-release buckle before every session

• Know where your belt sits — you should be able to locate and release it by feel alone

• If in doubt, ditch the weights — your safety is worth more than the cost of replacing them

Understanding when and how to use safety equipment is critical. Read our guide to freediving risks and safety.

📚 Educational Content Only: This guide is for educational purposes and does not replace professional freediving instruction. Before attempting any breath-hold training, equalization techniques, or depth diving, you must complete a certified freediving course with a qualified instructor (AIDA, PADI, SSI, Molchanovs, or FII). Never practice breath-holding in water without a trained safety buddy present.

Key Takeaways

• Proper weighting = neutral buoyancy at 10-15m for recreational diving

• Use the float test: waterline at eye level with a normal breath

• Rubber belts >>> webbing belts (stretch with wetsuit compression)

• Quick-release buckle is mandatory — practice using it

• Adjust weight when you change wetsuit thickness, water type, or target depth

• When in doubt, slightly underweight — easier to add than remove mid-session

Weighting is a foundational skill. Combined with proper fins, a good wetsuit, and the right mask, you have the equipment foundation for safe, efficient freediving.