AIAZHHow To Use
- Enter your age in years.
- Enter your resting heart rate in beats per minute (measure it first thing in the morning for best accuracy).
- Click "Calculate Heart Rate Zones" to see your personalized target zones.
- Use the zone ranges to guide your exercise intensity for different workout goals.
- Refer to the moderate and vigorous zones for general fitness guidelines.
Frequently Asked Questions
How do I measure my 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 30 seconds, and multiply by 2. A normal resting heart rate is 60-100 bpm for adults.
What is the Karvonen formula?
The Karvonen formula calculates target heart rate using Heart Rate Reserve: Target HR = ((Max HR - Resting HR) × %Intensity) + Resting HR. Max HR is estimated as 220 - age. This method is more personalized than the simple percentage of max HR method.
What heart rate zone should I train in?
For general fitness, train in the moderate zone (50-70% intensity). For improving cardiovascular fitness and burning more calories, incorporate vigorous zone training (70-85%). Beginners should start in the lower zones and gradually increase intensity.
What is a normal maximum heart rate?
Maximum heart rate is estimated as 220 minus your age. However, this is a population average and individual max heart rates can vary by 10-20 bpm. The most accurate way to determine your true max HR is through a graded exercise test.
Is my health data stored or shared?
No. All calculations are performed locally in your browser. Your age and heart rate data never leaves your device.
Can I use this for medical purposes?
This calculator provides general fitness guidelines only. If you have a heart condition or other health concerns, consult your doctor before starting an exercise program.
Karvonen Formula
Uses the Karvonen formula (Heart Rate Reserve method) which accounts for both age and resting heart rate for more accurate target zones.
Five Heart Rate Zones
See all five heart rate zones from very light to maximum intensity. Each zone corresponds to different fitness benefits.
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Your health data never leaves your device. All calculations happen locally in your browser with JavaScript.
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No account required, no email needed. Use the heart rate calculator unlimited times for free.
Find Your Target Heart Rate Zones for Optimal Exercise
Our free heart rate calculator uses the Karvonen formula to determine your personalized target heart rate zones. Training in the right heart rate zone helps you exercise more efficiently, whether your goal is fat burning, cardiovascular fitness, or performance improvement.
Understanding the Five Heart Rate Zones
Zone 1 (50-60%) is very light activity, ideal for warm-ups and recovery. Zone 2 (60-70%) improves basic endurance. Zone 3 (70-80%) enhances aerobic fitness. Zone 4 (80-90%) increases speed and power. Zone 5 (90-100%) is for maximum effort intervals.
Why Resting Heart Rate Matters
Your resting heart rate is a key indicator of cardiovascular fitness. A lower resting heart rate generally indicates better heart health and fitness. As you become fitter, your resting heart rate typically decreases. Tracking changes in your resting HR over time can show improvements in your fitness level.
Moderate vs Vigorous Exercise Intensity
The moderate zone (50-70% intensity) is suitable for daily exercise like brisk walking or cycling. The vigorous zone (70-85%) provides greater cardiovascular benefits in less time. Health guidelines recommend 150 minutes of moderate or 75 minutes of vigorous activity per week.