11 Essentials for Accurate Pulse Oximeter Readings

7. Correct finger placement and how long to wait for a stable reading

Place the probe on a clean middle or index finger and ensure the sensor covers the entire fingertip. The finger should sit comfortably and not be crushed by the clip. Hold the hand relaxed and supported at heart level while the device measures. Many users glance too soon; wait at least 30 seconds for the display to stabilize and consider 60 seconds for the most reliable value, especially if readings fluctuate. If the device shows a pulse rate that matches your expectation and remains steady, the SpO2 number is more trustworthy. If the pulse reading is erratic or absent, reposition the finger and try again. Keep the hand warm, and remove rings if they pinch the finger. For caregivers checking multiple people, adopt a consistent routine for finger choice and wait time; consistency reduces random variation across readings and makes trends easier to interpret.