SpO2 Oxygen Saturation Guide
Enter your pulse oximeter SpO2 reading to understand if it's normal, concerning, or requires emergency action.
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SpO2 Assessment
SpO2 (peripheral oxygen saturation) measures the percentage of hemoglobin in your blood that is carrying oxygen.
SpO2 ranges:
- 95%–100%: Normal for healthy adults
- 92%–94%: Mildly low — monitor closely, consult your doctor
- 88%–91%: Low — seek medical attention
- Below 88%: Dangerously low — seek emergency care
At high altitude, normal SpO2 may be lower:
- Sea level: 95%–100%
- 5,000 ft (1,500 m): 93%–98%
- 8,000 ft (2,400 m): 90%–95%
- 10,000 ft (3,000 m): 87%–93%
Factors that affect readings:
- Cold fingers or poor circulation can give falsely low readings
- Dark nail polish may interfere with the sensor
- Excessive movement during measurement
- Carbon monoxide poisoning can give falsely normal readings
Important: This is for informational purposes only. If you are experiencing breathing difficulty, chest pain, or confusion, call emergency services regardless of SpO2 reading.