Watts per Heartbeat Calculator
Your aerobic efficiency from power and heart rate
AI logs your meals from a photo. Diet & workouts in one app.Get the free appyour average power, e.g. 220
your average heart rate, e.g. 150
Watts per Heartbeat Calculator
Two riders can hold the same power, but the one doing it at a lower heart rate has the more efficient aerobic engine. Watts per heartbeat captures that in a single number: average power divided by average heart rate. Enter both and this calculator returns your watts per beat and the work done per beat. Track it on steady efforts to watch aerobic fitness improve over a training block.
Watts per heartbeat is average power divided by average heart rate — a simple index of how much external work each beat of your heart delivers. At the same heart rate, more watts per beat means a more efficient aerobic engine, so the number tends to rise as fitness improves. Compare it only at similar intensity, duration and conditions; it falls during a ride as cardiac drift pushes heart rate up.
Frequently Asked Questions
- What is watts per heartbeat?
- Watts per heartbeat is an aerobic efficiency index that divides your average power output by your heart rate. It shows how much work you produce for each beat, so a higher value means your cardiovascular system is delivering more output per unit of effort.
- How do I calculate watts per heartbeat?
- Divide your average power in watts by your average heart rate in beats per minute over the same effort. Riding at 200 watts and 160 bpm gives 1.25 watts per beat. Enter both numbers and the calculator returns your efficiency index.
- How do I interpret my watts-per-heartbeat number?
- Compare it across similar workouts: as aerobic fitness improves, you produce more watts at the same heart rate, so the value rises. It's most useful as a personal trend rather than an absolute benchmark, since it varies with effort length, heat and fatigue.