❤️ Health & Fitness

Heart Rate Zones Calculator

Find your 5 training zones — from recovery to maximum effort. Enter your age and resting heart rate to get personalised zones using the Karvonen method.

Personal details
years
bpm
Measure your resting heart rate first thing in the morning, before getting out of bed.
❤️ Maximum Heart Rate
-- Enter your details and click Calculate
--Resting HR
--Heart Rate Reserve
--Method Used

How heart rate zones work

Heart rate training zones divide your effort into five intensity levels based on your maximum heart rate. Training in the right zone helps you achieve specific fitness goals — from building endurance to improving speed and anaerobic capacity.

Max HR (simple): 220 − Age
Karvonen method: Target HR = ((Max HR − Resting HR) × Intensity %) + Resting HR
Heart Rate Reserve: Max HR − Resting HR
💙 Zone 1 — Recovery

50–60% of HRR. Very light effort. Used for warm-ups, cool-downs, and recovery days. Improves overall cardiovascular health without fatigue.

💚 Zone 2 — Aerobic Base

60–70% of HRR. Light effort, can hold a conversation. Builds aerobic endurance, burns fat, and forms the foundation for all higher-intensity work.

💛 Zone 3 — Tempo

70–80% of HRR. Moderate effort, harder to talk. Improves aerobic capacity and efficiency. The "sweet spot" for many endurance athletes.

🧡 Zone 4 — Threshold

80–90% of HRR. Hard effort, breathing is heavy. Increases lactate threshold. Used for interval training and race-pace workouts.

❤️ Zone 5 — Maximum

90–100% of HRR. All-out effort, cannot sustain for long. Builds power, speed, and anaerobic capacity. Use sparingly for short sprints.

📊 Karvonen vs 220-Age

The Karvonen method accounts for your resting heart rate, making it more personalised and accurate than the simple 220-age formula, especially for fit individuals with low resting HR.

Frequently asked questions

Heart rate training zones are intensity ranges based on your maximum heart rate. They help you train at the right intensity for your fitness goals — from easy recovery (Zone 1) to maximum effort (Zone 5).
The Karvonen method calculates heart rate zones using your resting heart rate and max heart rate. It's more accurate than the simple 220-age formula because it accounts for your individual fitness level.
Max heart rate (HRmax) is the highest number of beats per minute your heart can achieve. The common estimate is 220 minus your age, but the most accurate method is a stress test or field test.
Zone 1-2 for recovery and endurance, Zone 3 for aerobic fitness, Zone 4 for threshold training, and Zone 5 for maximum intensity sprints. Most endurance athletes spend 70-80% of their training in Zones 1-2.
No. This tool runs entirely in your browser. Your age, resting heart rate, and all calculations never leave your device. 100% private.