Blood Oxygen (SpO2) Altitude Impact Calculator
Enter altitude and health factors to calculate your blood oxygen saturation and assess hypoxia risk.
Denver: 5,280 ft, Everest Base Camp: 17,600 ft
Normal: 95-100%. Measure with pulse oximeter.
0 = just arrived, 7+ = well-acclimatized
How does altitude affect blood oxygen saturation?
At sea level: 95-100% SpO2. 5,000 ft: 90-95%. 8,000 ft: 85-92%. 12,000 ft: 75-85%. 15,000 ft: 65-75%. Every 1,000 ft above 5,000 ft drops SpO2 ~2-3%. Your body compensates by making more red blood cells (after 3-7 days), but initial drops can cause headaches, fatigue, nausea (acute mountain sickness).
What SpO2 is dangerous at altitude?
Normal: 95-100% (sea level). Mild hypoxia: 90-94% (5-8k ft). Moderatene hypoxia: 85-89% (8-12k ft) - strongest headache, fatigue. Severe: 80-84% - confusion, blue lips. Dangerous: <80% - requires immediate descent/oxygen. Below 70% = life-threatening.
How can I increase SpO2 at altitude?
1) Acclimatize: Spend 2-3 nights at 5k ft before going higher. 2) Diamox (acetazolamide): Raises SpO2 3-5% (prescription). 3) Deep breathing exercises: +2-3% immediately. 4) Stay hydrated (thick blood = lower SpO2). 5) Avoid alcohol/sleeping pills (suppress breathing). 6) Portable oxygen: +5-10% instantly.
Do athletes perform better or worse at altitude?
Endurance drops 1-2% per 1,000 ft above 5,000 ft due to lower oxygen delivery. Power/strength unafected below 10k ft. Some athletes train at 8-10k ft (live high, train low) to boost EPO and red blood cell count, improving sea-level VO2 max 3-5% after 3-4 weeks.