Heart Rate Zone Calculator
The Heart Rate Zone (HRZ) Calculator uses your age and resting heart rate to give you personalized heart rate zones based on the Karvonen formula. Whether you're running, lifting, or flowing through yoga, these zones help you target the right intensity from active recovery to peak performance.
Heart Rate Zone Calculator
Karvonen (HRR) or %Max with modern formulas. Fully client‑side.
Tip: If you know your **measured max HR** from a recent race or lab test, enter it for most accurate zones. Otherwise we’ll estimate from the chosen formula.
Max HR: — bpm
Method: —
HRR = Max − Resting. Karvonen applies your RHR so lower‑intensity zones reflect your individual baseline.
Guidance: Z1–Z2 aerobic base; Z3 steady/tempo; Z4 threshold; Z5 VO₂. Use RPE alongside HR for heat, terrain and fatigue.
Running Drills | Sendō
Running drills can be a game-changer. These simple, focused movements improve your form, increase your speed, and reinforce proper biomechanics.
Midori Sendō
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