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Find your training heart-rate zones from maximum heart rate estimates.
Find your training heart-rate zones from maximum heart rate estimates.
Enter values above and click Calculate — results will appear here with the formula explained.
Training intensity lives on a spectrum from recovery jogs to all-out intervals, and heart rate provides a live gauge of where you sit. The simple 220-minus-age maximum is crude (individual spread exceeds ±10 bpm) but serviceable without lab testing.
Adding your resting heart rate unlocks the Karvonen method, which measures intensity against your usable range rather than raw maximum. Fitter people have lower resting pulses, and Karvonen zones adjust accordingly — a genuinely meaningful refinement for anyone who knows their morning reading.
The five zones each train different physiology: Zone 1 (50–60%) drives recovery blood flow; Zone 2 (60–70%) builds mitochondrial base and fat oxidation — where 80% of endurance volume belongs; Zone 3 (70–80%) tempo work lifts sustainable pace; Zone 4 (80–90%) threshold intervals raise lactate clearance; Zone 5 (90–100%) sharpens VO2 max in short doses. Most recreational athletes invert this, living in Zone 3 gray zone that fatigues without adapting.
220-minus-age alternatives exist for better estimates: Tanaka (208 − 0.7×age) fits adults over 40 better, and the Haskell/Fox formula's ±12 bpm error band means field testing (a 20-minute all-out time trial, taking 95% of average HR) beats any equation when precision matters. Re-test max yearly — it declines roughly 1 bpm per year, and zones must follow.
Device reality check: wrist-optical sensors lag 10–20 seconds behind spikes and fail on intervals, tattoos and cold skin; chest straps track beat-to-beat. For Zone 2 base work optical is fine; for Zone 4–5 intervals, strap data prevents training blind. Also note cardiac drift — the same pace reads 5–10 bpm higher after an hour in heat, which is fatigue and dehydration, not fitness loss.
Safety framing: beta blockers and some calcium-channel blockers suppress heart-rate response, making zone math invalid without medical guidance; post-viral myocarditis risk means returning to Zone 4–5 only after clearance; and chest pain, faintness or palpitations override any zone — stop and seek care. Zones optimize healthy training; they never diagnose.
Find your training heart-rate zones from maximum heart rate estimates. Formula: Max HR ≈ 220 − age. Example: At age 35, max HR estimates at 185 bpm.
Training intensity lives on a spectrum from recovery jogs to all-out intervals, and heart rate provides a live gauge of where you sit. The simple 220-minus-age maximum is crude (individual spread exceeds ±10 bpm) but serviceable without lab testing.
Adding your resting heart rate unlocks the Karvonen method, which measures intensity against your usable range rather than raw maximum. Fitter people have lower resting pulses, and Karvonen zones adjust accordingly — a genuinely meaningful refinement for anyone who knows their morning reading.
The five zones each train different physiology: Zone 1 (50–60%) drives recovery blood flow; Zone 2 (60–70%) builds mitochondrial base and fat oxidation — where 80% of endurance volume belongs; Zone 3 (70–80%) tempo work lifts sustainable pace; Zone 4 (80–90%) threshold intervals raise lactate clearance; Zone 5 (90–100%) sharpens VO2 max in short doses. Most recreational athletes invert this, living in Zone 3 gray zone that fatigues without adapting.
220-minus-age alternatives exist for better estimates: Tanaka (208 − 0.7×age) fits adults over 40 better, and the Haskell/Fox formula's ±12 bpm error band means field testing (a 20-minute all-out time trial, taking 95% of average HR) beats any equation when precision matters. Re-test max yearly — it declines roughly 1 bpm per year, and zones must follow.
Device reality check: wrist-optical sensors lag 10–20 seconds behind spikes and fail on intervals, tattoos and cold skin; chest straps track beat-to-beat. For Zone 2 base work optical is fine; for Zone 4–5 intervals, strap data prevents training blind. Also note cardiac drift — the same pace reads 5–10 bpm higher after an hour in heat, which is fatigue and dehydration, not fitness loss.
Safety framing: beta blockers and some calcium-channel blockers suppress heart-rate response, making zone math invalid without medical guidance; post-viral myocarditis risk means returning to Zone 4–5 only after clearance; and chest pain, faintness or palpitations override any zone — stop and seek care. Zones optimize healthy training; they never diagnose.
At age 35, max HR estimates at 185 bpm. With a 55 resting pulse, Zone 2 spans 132–146 bpm by Karvonen — noticeably different from the plain-percentage 111–130. An 80/20 week at this fitness might be four 45-minute Zone 2 runs plus one interval session touching Zone 4–5.
Formulas are standard public references (see our methodology). External standards are cited in the text where they apply.
Last reviewed: September 2026 · Report an error