Target Heart Rate Calculator
Please enter valid age and resting heart rate.
What Is a Target Heart Rate Calculator?
A target heart rate calculator determines your ideal heart rate zones for different training intensities — from light activity to peak effort — using your age and resting heart rate.
Formula Used (Karvonen Formula)
Max Heart Rate = 220 − Age
Target HR = [(Max HR − Resting HR) × %Intensity] + Resting HR
The Karvonen formula accounts for your resting heart rate (heart rate reserve), which typically gives more personalized zones than simply using a percentage of max heart rate alone.
How to Use This Calculator
Enter your age and resting heart rate (measured first thing in the morning before getting up is most accurate), then click "Calculate Heart Rate Zones" to see your training zones from light activity through peak effort.
What Each Zone Is Used For
Light (50-60%): Warm-up and recovery. Fat Burn (60-70%): Long, steady-state cardio. Cardio (70-80%): Improving cardiovascular fitness. Peak (80-90%): High-intensity intervals and performance training.
Frequently Asked Questions
How do I measure my resting heart rate?
Measure it first thing in the morning, before getting out of bed, for the most accurate baseline reading.
Is the "220 minus age" formula always accurate?
It's a widely used estimate, but individual max heart rate can vary by 10-20 beats per minute from this formula — a fitness professional can help with more precise testing if needed.
Which zone is best for weight loss?
The "fat burn" zone uses a higher percentage of fat for fuel, but total calories burned (which increases with intensity) matters more for overall weight loss than the specific zone.
Should beginners train in the peak zone?
Beginners generally should build a base in lower zones first before adding high-intensity peak zone training to reduce injury risk and support proper adaptation.