How to use it
- Enter your age in years.
- Enter your resting heart rate (bpm).
- Press Calculate.
- Read the lower and upper bounds displayed.
Your Zone 2 heart‑rate range tells you the beats‑per‑minute window where you train aerobic, improve endurance, and burn fat while staying comfortable enough to hold a conversation. The calculator first estimates your maximum heart rate with the standard 220‑age formula, then uses your resting heart rate to pinpoint the lower and upper limits of Zone 2. The lower bound marks the point where effort becomes moderate; the upper bound is the threshold before you enter higher intensity zones. Knowing these numbers lets you set treadmill, bike, or run targets, monitor workouts with a watch, and adjust effort day‑to‑day for consistent progress. The result updates instantly, so you can experiment with different paces and see how quickly you stay within the optimal zone.
Pro tips
- Round the results to the nearest whole beat for easier use with most monitors.
- If your resting rate changes, recalculate to keep the zone accurate.
- Enter age as a whole number; decimals can skew the max‑HR estimate.
- Use the lower bound for warm‑ups and the upper bound for steady‑state cardio.
Real-life examples
- A beginner runner wants to stay in the aerobic zone while building mileage.
- A cyclist plans weekly long rides and needs the exact heart‑rate window for endurance training.
- A busy professional tracks workouts on a smartwatch and wants quick zone numbers without a lab test.
Case study
Maria, 38, with a resting rate of 58 bpm, used the calculator and discovered her Zone 2 was 112‑128 bpm. By training within that window for three weeks, she reported smoother runs, less fatigue, and a noticeable boost in weekly mileage.