Normal Oxygen Saturation Values

Normal Oxygen Saturation Ranges by Age Group

The American Thoracic Society recommends that healthy adults typically have a target range of 94-98% oxygen saturation, while children younger than 1 year old should maintain oxygen saturation above 90%, and children 1 year and older should maintain oxygen saturation above 93% 1, 2
In infants younger than 1 year, hypoxemia is defined as oxygen saturation ≤90% for 5% or more of recording time, or three independent measurements of oxygen saturation ≤90% 1
Children 1 year and older typically have a mean oxygen saturation of 97.6% (±0.7%) during wakefulness 1

All age groups experience greater variation in oxygen saturation during sleep compared to wakefulness 2
The mean minimum oxygen saturation "nadir" during normal sleep is approximately 90.4% (±3.1%) 2
Adults aged 20-30 years typically spend 10% of the night with oxygen saturation below 94.8% and half the night below 96.3% 2

Pulse oximetry is sufficient for diagnosing hypoxemia in pediatric patients, with arterial blood gas analysis rarely needed 1
Most experts emphasize the importance of maintaining oxygen saturation above 90% for most acutely ill patients 5
Sudden exposure to oxygen saturation below 80% can cause altered consciousness even in healthy individuals 5

Obese patients with sleep apnea can desaturate to very low levels (often below 70%) 2
In very rare cases, conditions affecting hemoglobin (carboxyhemoglobin, methemoglobin, sickle cell disease) may require arterial blood gas analysis instead of pulse oximetry 1