Is 94 blood oxygen normal?
Awake and resting, 94 is a little under the normal range of 95 to 100, so recheck sitting still with warm hands. As a watch night average at sea level it's typical, about the 5th percentile for a 40-year-old.
Recheck: sit still for a few minutes, warm hands, no nail polish on that finger. At 92 or lower, call your doctor.
About the 5th percentile at sea level for a 40-year-old, and about the 50th in Denver, among Apple Watch wearers.
In 350 people with normal sleep studies, the lowest point of the night averaged about 90, and most stayed between about 84 and 97.
94 is the number with two lives. Awake and resting, it’s one point under the normal range of 95 to 100, so recheck: sit still for a few minutes, warm your hands, take off dark polish and wait until the number stops changing. If it settles at 95 or more, you’re done. If it drops to 92 or lower, call your doctor.
As a watch’s night average, 94 is common. At sea level it sits at about the 5th percentile for a 40-year-old, low but still inside the typical range of about 93.5 to 98.4. In Denver it’s right in the middle, about the 50th percentile, because Denver’s elevation takes about 1.9 points off a typical night. Your Denver 94 is a sea-level 96.
As the lowest point of a night, 94 is better than most healthy sleepers manage: in 350 people with normal sleep studies, the lowest point averaged about 90. If you have darker skin, an oximeter’s 94 may sit a little high, so give how you feel the final say.
The device. A cleared finger oximeter can be off by about 3 points, a watch by about 2, and more when oxygen is low: below 88, an Apple Watch Series 7 was off by about 6 in 9 young adults.
Darker skin. Pulse oximeters can show too high on darker skin. In hospital patients whose oximeter showed 92 to 96, true oxygen was under 88 for 11.7% of Black patients' readings and 3.6% of White patients'.
Elevation. At Denver's 5,280 feet, a typical watch night sits about 1.9 points lower and a typical day about 1.4 lower. Above 8,200 feet the number can't tell you if you're getting sick, and symptoms decide.
When to get help
Call 911 if you have trouble breathing, chest pain or pressure that doesn't go away, new confusion, can't stay awake, or your lips, nail beds or skin look pale, gray or blue, whatever the number says.
Open this in Your number Is my blood oxygen normal? Take the quiz
7 sources
- MedlinePlus, Pulse Oximetry, US National Library of Medicine, updated September 12, 2024medlineplus.gov
- Shapiro I and others, Pulse oximetry values from 33,080 participants in the Apple Heart and Movement Study, npj Digital Medicine, 2023pmc.ncbi.nlm.nih.gov
- Gries RE and Brooks LJ, Normal oxyhemoglobin saturation during sleep, Chest, 1996europepmc.org
- Sjoding MW and others, Racial bias in pulse oximetry measurement, New England Journal of Medicine, 2020pmc.ncbi.nlm.nih.gov
- Jiang and others, an Apple Watch Series 7 and a medical-grade finger oximeter against blood tests in 9 healthy adults under controlled low oxygen, 2026pmc.ncbi.nlm.nih.gov
- Gries RE and Brooks LJ, Normal oxyhemoglobin saturation during sleep: how low does it go?, Chest, 1996europepmc.org
- US Food and Drug Administration, Pulse oximeter basics, content current as of March 26, 2025fda.gov
