Enter your SpO2 reading to instantly see if your blood oxygen level is normal, borderline, or requires medical attention.
Medical Disclaimer: This tool is for informational purposes only and is not a substitute for professional medical advice. If you are experiencing breathing difficulties or have a low SpO2 reading, consult a qualified healthcare provider immediately.
Enter the percentage value from your pulse oximeter or smartwatch. Typical range: 90–100%.
Optimal oxygen levels
Acceptable, healthy range
Mildly low — consider medical advice
Consult a doctor soon
Seek emergency medical care immediately
A normal blood oxygen saturation (SpO2) level for a healthy adult is 95–100%. Most people sit at 97–99% at sea level. Readings consistently below 95% may warrant medical attention, and anything below 90% is considered a medical emergency that requires immediate care.
Low SpO2 can result from many conditions including respiratory infections (like pneumonia or COVID-19), asthma, COPD, sleep apnea, heart conditions, anaemia, high altitude, and pneumothorax (collapsed lung). Temporarily low readings can also occur from cold fingers, poor sensor contact, or nail polish when using a pulse oximeter. If you have a sustained low reading, seek medical evaluation.
SpO2 is most commonly measured non-invasively using a pulse oximeter—a small device clipped to a fingertip that shines light through the skin and calculates how much is absorbed by oxygenated versus deoxygenated haemoglobin. Modern smartwatches and fitness trackers also estimate SpO2, though they are generally less accurate than dedicated medical-grade pulse oximeters.
Seek emergency medical care immediately if your SpO2 drops below 90%, or if you experience difficulty breathing, chest pain, confusion, or bluish discolouration of lips or fingernails (cyanosis) at any SpO2 level. If your reading is 90–94%, contact a doctor promptly. If you are healthy but see a reading of 93–94%, retake the measurement after warming your hands and ensuring good sensor contact before acting.
HC Webhook automatically sends your blood oxygen readings to any webhook endpoint, enabling continuous monitoring and alerts.
