Find your personalized training zones using the proven Karvonen formula. Train smart by knowing exactly when you're warming up, burning fat, or pushing toward maximum effort.
Enter your age and resting heart rate — zones update live.
Recommended Training Range
Max HR
190 bpm
Reserve (HRR)
125 bpm
Fat-Burn Mid
146 bpm
Aerobic Mid
159 bpm
| Zone | Intensity | Range (bpm) | Best For |
|---|
Typical Resting Heart Rates
Lower RHR generally indicates better cardiovascular fitness.
Training Tips
The Formula
We use the Karvonen formula — the gold standard for personalized training zones. Unlike a flat percentage of max heart rate, Karvonen accounts for your heart rate reserve: the gap between your resting and maximum heart rate.
A fitter person with a lower resting heart rate will get a different target than someone with the same age but a higher resting rate — even at the same training intensity.
Karvonen Equation
About This Tool
A target heart rate calculator tells you how fast your heart should beat during exercise for a specific training goal — fat loss, endurance, performance, or recovery. Most people unknowingly train at the wrong intensity, missing the benefits they're chasing.
This tool uses the Karvonen method, named after Finnish physiologist Martti Karvonen who developed it in the 1950s. It's more personalized than the simple "220 − age × %" approach because it factors in your resting heart rate — a strong proxy for cardiovascular fitness.
The result is five training zones spanning recovery to all-out effort. Knowing which zone you're in turns every workout into deliberate practice instead of guesswork — the difference between exercising and training.
Five Training Zones
From warm-up to max effort — every workout has a home.
Karvonen Accuracy
Uses heart rate reserve for more personalized targets.
Live Recalculation
Drag the sliders or type — every zone updates instantly.
Visual Range Chart
See all five zones side-by-side, scaled to your max HR.
Goal-Aware
Each zone is labeled with what it's best for — fat burn, endurance, VO₂.
Universal
Works for running, cycling, rowing, swimming — any aerobic activity.
Personalized training zones in under 30 seconds.
Measure first thing in the morning, before getting out of bed. Count for 60 seconds. Average 3–5 days for accuracy.
Type or use the sliders. Both inputs feed into the Karvonen formula directly.
Each zone shows its bpm range and what it's best for — pick the one that matches your workout goal.
Use a chest-strap monitor for accuracy. Stay in your target zone for the bulk of the workout — drift out, drift back.
As you get fitter, resting HR drops. Re-run the calculator monthly to keep your zones accurate.
Most weeks: 80% Zones 1–2, 20% Zones 4–5. This polarized approach beats grinding in the middle.
Everything you need to know about heart rate training.
The Karvonen formula: Target HR = ((Max HR − Resting HR) × intensity%) + Resting HR. It uses your heart rate reserve, which makes it more personalized than the simpler "percent of max HR" method.
We use the classic 220 − age. Other formulas (Tanaka's 208 − 0.7 × age) can be slightly more accurate for older adults but differ by only a few bpm. The most accurate way is a maximal effort test under medical supervision.
Zone 2 (60–70% of max) burns the highest percentage of calories from fat, but Zones 3–4 burn more total calories, which usually wins for weight loss. For metabolic health and endurance, Zone 2 is the foundation; for time-efficient fat loss, mix in Zone 4 intervals.
Measure first thing in the morning before getting out of bed. Count beats for 60 seconds. Average over 3–5 mornings — daily values vary 5–10 bpm with sleep, stress and hydration. Typical adult RHR is 60–80 bpm; athletes often see 40–60 bpm.
These are estimates. If you have heart disease, take beta-blockers (which suppress HR), are new to exercise, or are over 40 and sedentary, consult a physician before training in higher zones. Chest pain, dizziness, or unusual breathlessness during exercise are reasons to stop immediately.
Wrist-based optical HR monitors typically read ±5 bpm and lag during quick intensity changes. Chest straps are the gold standard for accuracy — pick one if you do interval work. Many smartwatches use their own zone formulas (often %MHR rather than Karvonen), so the labels may differ.
For most goals, follow the polarized model: roughly 80% of your weekly minutes in Zones 1–2 (easy/conversational) and 20% in Zones 4–5 (hard intervals). The grey zone in the middle gets popular but produces the least adaptation per unit of fatigue.