Target Heart Rate Calculator

Calculate your target heart rate zones using the Karvonen formula. Find your ideal exercise intensity for fat burning, cardio, and peak performance.

Karvonen Formula

Target HR = ((Max HR − Resting HR) × Intensity%) + Resting HR
Max HR = 220 − Age

The Karvonen method uses your heart rate reserve (HRR = Max HR − Resting HR) to calculate target zones. It's more personalized than simple percentage-of-max methods because it accounts for your fitness level through resting heart rate.

Example: Age 30, Resting HR 65 bpm
Max HR = 220 − 30 = 190 bpm
Heart Rate Reserve = 190 − 65 = 125 bpm
Zone 3 (70%): (125 × 0.70) + 65 = 153 bpm
Zone 3 (80%): (125 × 0.80) + 65 = 165 bpm

Heart Rate Training Zones

ZoneIntensityBenefit
Zone 150-60%Recovery, warm-up
Zone 260-70%Fat burning, endurance base
Zone 370-80%Aerobic fitness, cardio
Zone 480-85%Anaerobic threshold, speed

How to Measure Resting Heart Rate

Measure your resting heart rate first thing in the morning before getting out of bed. Place two fingers on your wrist or neck, count the beats for 60 seconds (or 15 seconds × 4). Take measurements on 3 consecutive days and use the average.

FAQ

What zone should I exercise in?

Zone 2 (60-70%) is ideal for fat burning and building endurance. Zone 3 (70-80%) improves cardiovascular fitness. Mix zones for best overall fitness.

Is the 220 minus age formula accurate?

It's a reasonable estimate for most people. Individual max heart rate can vary by ±10-12 bpm. For more accuracy, a supervised stress test is recommended.

⚠️ Medical Disclaimer: This calculator provides estimates for informational purposes only. If you have a heart condition or are starting a new exercise program, consult your doctor first. Stop exercising if you feel dizzy, short of breath, or have chest pain.

Last updated: 2026-08-08