Depth Pressure Calculator
Understand how pressure affects your body underwater. See Boyle's Law in action and learn why equalization matters most in the first 10 meters.
Settings
Average: 6L for men, 4-5L for women
Pressure at 10m
2.03 bar | 29.4 PSI
Lung Volume Compression
Air Space Compression
All air spaces (mask, sinuses, middle ear) compress by:
This is why you must equalize - to add air and prevent squeeze
Why First 10m Matters Most
From 0-10m, pressure doubles (1ā2 ATM), compressing air spaces by 50%. From 10-20m, pressure only increases by 50% (2ā3 ATM). This is why equalization is most critical in shallow water and why most ear injuries happen near the surface.
Pressure at Different Depths
| Depth | Pressure | Lung Volume | Compression | Pressure Change |
|---|---|---|---|---|
| 0m | 1 ATM | 6.0L | 0% | ā |
| 10m | 2 ATM | 3.0L | 50% | +100% |
| 20m | 3 ATM | 2.0L | 67% | +50% |
| 30m | 4 ATM | 1.5L | 75% | +33% |
| 40m | 5 ATM | 1.2L | 80% | +25% |
| 50m | 6 ATM | 1.0L | 83% | +20% |
| 60m | 7 ATM | 0.9L | 86% | +17% |
| 70m | 8 ATM | 0.8L | 88% | +14% |
| 80m | 9 ATM | 0.7L | 89% | +13% |
| 90m | 10 ATM | 0.6L | 90% | +11% |
| 100m | 11 ATM | 0.5L | 91% | +10% |
Notice how the pressure change percentage decreases with depth. The first 10m has 100% pressure increase, while 20-30m only has 33% increase. This demonstrates why the shallow zone is the "danger zone" for equalization.
Understanding Boyle's Law
The Formula
At constant temperature, the pressure and volume of a gas are inversely proportional. When pressure doubles, volume halves.
What This Means for Freediving
- ā¢Your lungs compress as you descend, reducing buoyancy
- ā¢Air in your mask and sinuses also compresses, causing squeeze if not equalized
- ā¢On ascent, air expands - never hold your breath after breathing compressed air
- ā¢The first 10m has the greatest pressure change - equalize early and often