According to the Sleep Foundation, a normal heart rate during sleep drops to between 40 and 50 beats per minute (bpm) . However, there is variability between individuals, and a normal sleeping heart rate can vary depending on factors such as age, fitness level, and sex. For most healthy adults, a normal sleeping heart rate is typically between 50-70 bpm, which can be lower for athletes or physically active individuals. It is important to note that some people have heart rates outside these ranges and are still perfectly healthy. Children tend to have higher heart rates than adults, and their sleeping heart rate might range from 67 to 89 bpm.

It is also worth noting that heart rate can vary depending on the phase of sleep. During light sleep, heart rate gradually slows to its resting rate, and during deep sleep, heart rate slows to about 20% to 30% below the resting heart rate. During REM sleep, heart rate can vary quite a bit depending on the activity level occurring in the dream.

If your heart rate consistently exceeds the normal range while you’re asleep, it might indicate an underlying issue, such as sleep apnea, arrhythmia, or another sleep-related disorder. It is recommended to consult a healthcare professional if you suspect your heart rate during sleep is unsafe.