What is a pulse oximeter?

A pulse oximeter is a small device that you place your finger snugly inside (most require nail side up), and within seconds it lights up with numbers indicating your blood oxygen level and heart rate. Most healthy people will get an oxygen reading around 95 to 98 percent. Some people with existing health conditions may have a lower normal reading. You should check in with your doctor if the number falls to around 93 or 92 or lower.

The device will also show your heart rate. A normal resting heart rate for adults ranges from about 60 to 100 beats per minute, although athletes with a higher cardiovascular fitness will have a lower pulse.

The device works better with warmer hands than cold hands. And because oxygen levels can fluctuate, consider taking measurements a few times a day. Also try it in different positions, such as while lying flat on your back or while walking. Keep notes to share with your doctor if needed.