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.
Get personalized training zones using Karvonen (HRR) or % Max HR. Great for Zone 2 work, tempo, and interval planning.
Tip: If you know your measured max HR from a recent race or lab test, enter it for the most accurate zones. Otherwise we'll estimate from the chosen formula.
Max HR: — bpm
Method: —
HRR (Heart Rate Reserve) = Max − Resting. Karvonen uses HRR so easier zones match your baseline instead of a generic chart.
Note: Formulas are estimates. Always pair zones with RPE (how it feels) — especially in heat, hills, or fatigue.
Guideline: Z1–Z2 = easy/aerobic base; Z3 = steady/tempo; higher zones = threshold & VO₂ work. Most endurance plans keep ~70–80% of training in the lower zones.
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Bike Fit
Gears
Power
Routes Bike Fit Assistant Quick starting points for size & contact points. Refine with a pro fit as you progress. Units cm
in Height Inseam Measure barefoot from floor to groin. Riding Style Road / Endurance
Gravel
MTB (Trail/XC)
Tri / TT
Commuter / Hybrid Frame Size
—
— Saddle Height
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