📌 Overview

Estimate your heart-rate training zones using the Karvonen formula, based on your max and resting heart rate. Perfect for runners, cyclists and HIIT training.

❤️ Heart Rate Zone Calculator

Estimate your heart-rate training zones using the Karvonen formula, based on your max and resting heart rate. Perfect for runners, cyclists and HIIT training.

Age (years)

Resting HR (bpm)

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📋 How to Use

Enter your age (used to estimate max heart rate).
Measure and enter your resting heart rate (morning, before getting up works best).
Click Calculate to see all five zones.
Use the zone ranges to guide your workout intensity.

❓ FAQ

What is the Karvonen formula?

Target HR = ((Max HR − Resting HR) × intensity%) + Resting HR. It personalises training zones using your resting heart rate, which the simpler 220−age method ignores.

How do I find my resting heart rate?

Take your pulse first thing in the morning, still lying down, for 30–60 seconds. A typical adult resting rate is 60–80 bpm.

Which zone should I train in?

Zone 2 (60–70%) builds aerobic base and burns fat; Zone 4–5 (80–90%+) improves speed and VO2 max but cannot be sustained long. Most people mix zones across the week.

❓ More Questions

How does the Karvonen formula differ from 220 − age?

The 220 − age method only estimates max heart rate and ignores each person’s resting heart rate. The Karvonen formula incorporates resting HR, giving target zones that better match your personal fitness.

Which zone should I train in to burn fat?

Zone 2 (about 60%–70% intensity) is best for fat-burning and building an aerobic base; Zones 4–5 are high-intensity and hard to sustain, mainly improving speed and VO2 max.

💡 Use Cases

🏃

Fat-burn runs

Hold Zone 2 for steady-state cardio.

🚴

Interval training

Push into Zone 4–5 for reps.

💓

Recovery

Keep easy days below Zone 2.

🔗 Related Tools

📖 Deep Dive: Heart Rate Zone Calculator

Why use heart-rate zones

Training by feel alone makes it easy to train too lightly or too hard. Heart-rate zones quantify intensity into five bands so you know exactly what each session is training.

The Karvonen formula

Target HR = (Max HR − Resting HR) × intensity% + Resting HR. Max HR is commonly estimated as 220 − age (a more precise option is 208 − 0.7 × age).

The five zones

Zone 1 (50%–60%): warm-up, recovery

Zone 2 (60%–70%): fat-burn, aerobic base

Zone 3 (70%–80%): aerobic endurance

Zone 4 (80%–90%): anaerobic threshold, speed

Zone 5 (90%–100%): sprint, max output

Cautions

The formula gives estimates; medication, caffeine and sleep all affect actual heart rate

A chest strap or watch is more accurate than a phone

For reference only; consult a professional before starting a new program