What is a good resting heart rate, and why every device shows a different one

A friend’s Oura says their resting heart rate is 48. Your Apple Watch says yours is 58. For a moment you feel ten beats less fit than them. Then you borrow a Garmin for a week and it tells you 52.

Nothing about your heart changed that week. What changed is the moment each device chose to call your heart resting. Here is what a good resting heart rate actually is, when each device takes its reading, and which number to trust.

What a good resting heart rate actually is

The clinical answer is simple. The American Heart Association puts a normal adult resting heart rate at 60 to 100 beats per minute, measured sitting or lying down while you are calm and well. It adds that a lower rate is common in athletes, and Mayo Clinic notes that very fit athletes can sit closer to 40.

Notice the conditions in that definition: awake, still, calm. Cleveland Clinic says it plainly: resting means sitting or lying down, but awake. Your heart goes lower still when you sleep, and that one detail is where the devices split.

Inside the normal range, there is no prize for the lowest number. Genetics, age, medication and years of training all set where you sit. What does carry meaning is the long-run trend. Across 46 studies pooled in a 2016 meta-analysis, each extra 10 beats per minute of resting heart rate was associated with about a 9 percent higher risk of death from any cause. The authors’ estimate after correcting for publication bias was smaller, about 4 percent, and it is an association, not proof that lowering the number causes anything. But it is the reason a resting heart rate that drifts down over months of training is good news.

When each device takes the reading

Every major wearable reports a resting heart rate, and every one defines “resting” its own way.

Read the first column. Apple is the only one that keeps sleep out by design: its own white paper describes the number as an estimate of your lowest heart rate during rest while awake, which happens to match the clinical definition. Everyone else leans on the night. WHOOP and Oura measure only during sleep, Fitbit gives sleep priority, and Garmin’s lowest 30 minutes of the day will, for anyone who wears it to bed, usually come from the small hours. Garmin even warns that its estimate is less accurate if you take the watch off overnight.

Google says the quiet part out loud about Fitbit: your sleeping heart rate is often lower than your resting heart rate. That is the whole gap in one sentence.

Why the gap between devices keeps moving

If the difference were a fixed offset, you could subtract it and move on. It is not, because the night and the day respond to different things.

• Your heart rate
• Awake reading (Apple)
• Sleep reading (WHOOP, Oura)

Illustrative shapes, not measured data. One evening to the next.

A sleep-based number reacts to your evening. Oura lists late meals, caffeine, alcohol and exercise close to bedtime among the things that push resting heart rate up, and Google adds stress, fever, air temperature and some medications. Have two glasses of wine and a warm bedroom, and a sleep-based device can read several beats high the next morning while an awake estimate taken from a calm afternoon barely moves. So the gap between two devices widens and narrows with your life, which is exactly why a reading from one cannot be converted into a reading from the other.

There is a knock-on effect, too. If your watch sets heart rate zones by heart rate reserve, your resting rate is one of the two endpoints, so a resting number taken at a different moment shifts every zone. And it is one of the inputs behind the health age and fitness age estimates, which is why those move when your resting rate does.

Reading your own number

The useful version of resting heart rate is the boring one: your device, worn the same way, compared with itself.

• Read the weekly line, not the morning. Garmin shows a rolling seven-day average for a reason. One high morning is noise; a week that drifts is a signal.
• Know what “high for you” means. Oura’s Readiness starts to dip when your resting rate runs 3 to 5 beats above your usual average, which is a sensible threshold to borrow whatever you wear.
• Expect the slow good news. Regular aerobic training tends to pull resting heart rate down over months, not days. If you are building fitness, watch the quarter, not the week.
• Know when it is not a fitness question. A resting rate that stays above 100, or a low rate that comes with dizziness, fainting or unusual tiredness, belongs with a doctor, not a dashboard.

This is how Fit, the cross-brand fitness competition app, handles it, and it is ours, so weigh this accordingly. Fit reads resting heart rate from whichever tracker you wear and shows today’s number against your own normal, learned over time. On a crew’s board it appears only as health context, ordered low to high for reference and never as a podium, with a note that trackers measure at different moments, so small gaps between devices are a tie. What Fit actually ranks is effort, using the units that survive the jump between brands.

What to do with this

1. Pick one device and read its seven-day average. A single morning tells you little. The weekly line tells you a lot.
2. Wear it to bed. Sleep-based numbers need the night, and Garmin says its estimate is less accurate if the watch comes off overnight.
3. Treat a few beats above your normal as a nudge. Two or three days running high is your cue for an easier day and an earlier night. A rise that does not settle, or any symptoms, is a reason to call a doctor.
4. Never compare your number with a friend’s. Different devices pick different moments, and even on the same device, genetics and age spread healthy people widely. Read your HRV the same way: against yourself.