What Is a Normal Sleeping Heart Rate?

Fitness trackers have turned all of us into amateur heart monitors. You wake up, glance at your wrist, and there it is: your lowest heart rate of the night, sitting at a number you are not quite sure how to read. Is 48 good? Is 70 too high? The short version is that your heart slows down while you sleep, and for most adults, it settles somewhere below the daytime resting rate. What counts as normal shifts with your age, your fitness and what your heart was up to before bed. Here is how to make sense of your own number.

First, a quick distinction. Your resting heart rate is how fast your heart beats when you are awake but relaxed, sitting still, perhaps with a cup of tea. Your sleeping heart rate is what it does once you are actually asleep, and it is usually lower again. For most healthy adults, resting heart rate sits between 60 and 100 bpm. During sleep, your nervous system winds down, and your heart follows, so that the number typically falls, often landing somewhere around 40 to 60 bpm. Very fit people and athletes can sit lower still.

There is no single magic figure. A healthy sleeping heart rate depends on your baseline, and it is completely normal for it to sit well below your daytime rate. Tracking it over several nights rather than fixating on a single reading gives you a truer picture. This is roughly why doctors sometimes measure heart rate across a full 24 hours instead of relying on a single clinic check. You can take your own pulse using the NHS method or read it off a fitness watch.

Heart rate is highest in babies and slows as we grow. Newborns can run well over 100 bpm even at rest, while a healthy teenager lands close to adult figures. Every age group drops lower again during sleep. The ranges below bring together children’s awake figures from a large systematic review, children’s sleeping data and adult resting norms. Treat them as typical ranges, not hard cut-offs:

Adult sleep rates are hard to pin down to a fixed range because they depend so heavily on your resting rate and fitness. As a rule of thumb, expect your sleeping heart rate to sit below your waking resting rate.

Your heart rate does not hold steady while you sleep. It moves with the stages of your sleep cycle. Not long after you drop off, it starts to slow. It reaches its lowest point in deep sleep, when your body is at its most settled. Then it climbs again during REM sleep, the dream-heavy stage, where it can briefly reach a rate close to your waking rate.

If you have ever jolted awake from a vivid dream with your heart going, that is REM doing its thing, and it is perfectly normal. For more on what those dreams might be telling you, our Dream Encyclopaedia is a fun rabbit hole.

Plenty of everyday things nudge your sleeping heart rate up or down. Here are a few of the usual suspects:

• Fitness: Regular exercise strengthens your heart, so it can do the same job with fewer beats. Fitter people tend to have lower resting and sleeping rates.
• Stress and anxiety: A wound-up mind keeps your body on alert, and prolonged stress can push your nighttime heart rate up.
• An irregular bedtime: Even shifting when you go to sleep can raise your resting heart rate for a day or two, so a steady routine helps.
• Food, drink and caffeine: A big or late meal makes your body work harder overnight, and what you eat can affect how your heart responds. Caffeine and alcohol are common culprits, too, which is where our guide to caffeine and sleep comes in.
• Pregnancy: The heart works harder, so a higher resting and sleep heart rate is expected. Where it is safe to do so, staying active can support healthy heart-rate patterns.
• Temperature, illness and medication: A warm room, a fever, or certain medicines can all shift your numbers, usually just while they last.

For most people, a heart rate that dips low overnight is a good sign rather than a worry. Plenty of fit, healthy adults sleep happily in the 40s. What matters more is a clear change from your own normal, or a number that turns up alongside symptoms.

It is worth speaking to your GP if your sleeping heart rate is regularly above 100 bpm, or if a low rate leaves you dizzy, faint or short of breath. The same goes for a pounding, racing or irregular beat at night. None of this is cause for panic, and a fitness tracker is not a medical device, but a doctor can check whether anything needs a closer look. If your heart ever worries you, get it checked rather than second-guessing a watch.

Because exercise shapes your resting and sleeping heart rate, it helps to know your numbers when you are working hard, too. When you exercise, your heart beats faster to get oxygen where it is needed.

A rough guide to your maximum heart rate is 220 minus your age, so around 180 bpm for a 40-year-old. Moderate effort usually sits at roughly 64 to 76 percent of that maximum, and vigorous effort at about 77 to 93 percent. It is only an estimate; treat it as a ballpark figure. The fitter you get, the more efficient your heart becomes, which tends to show up over time as lower resting and sleeping heart rates. For more on winding down for a better night, see our guide on how to sleep better at night.