Target Heart Rate Calculator
Calculate training heart rate zones
About the Target Heart Rate Calculator
Training by heart rate keeps your effort honest — too easy and you stall, too hard and you burn out. This calculator finds your personal training zones using the Karvonen method, which factors in your resting heart rate rather than relying on age alone, for ranges tailored to your fitness.
Runners, cyclists, and gym-goers use it to train deliberately: staying in the fat-burning zone for steady cardio, or pushing into the aerobic zone to build endurance. By starting from your heart rate reserve — the gap between your maximum and resting rates — it gives more individualized targets than a simple percentage of max heart rate.
How to Use the Target Heart Rate Calculator
- Enter your age (used to estimate your maximum heart rate).
- Enter your resting heart rate in beats per minute.
- Read your estimated maximum heart rate.
- Use the fat-burning and aerobic zone ranges to guide your workout intensity.
Why Use ToolForge’s Target Heart Rate Calculator
- It uses the Karvonen heart-rate-reserve method, which incorporates your resting heart rate for more personalized zones than an age-only formula.
- It reports concrete beats-per-minute ranges for the fat-burning and aerobic zones, so you know exactly what to aim for on a monitor.
- It estimates your maximum heart rate for you from your age, so you do not need to test it.
- Calculations are instant and run entirely in your browser.
Frequently Asked Questions
What is the Karvonen method?
The Karvonen method calculates target heart rate using your heart rate reserve — the difference between your maximum and resting heart rates — rather than a flat percentage of maximum. Because it includes your resting rate, it produces zones tailored to your individual fitness level.
How is maximum heart rate estimated?
This calculator uses the common estimate of 220 minus your age. It is a population average, so your true maximum may differ by several beats; for precision, a supervised stress test is the gold standard, but the estimate works well for everyday training.
What is the difference between the fat-burning and aerobic zones?
The fat-burning zone (a lower-intensity range) emphasizes steady effort where a higher share of energy comes from fat. The aerobic zone is more intense, building cardiovascular endurance. Both are useful; the right one depends on your workout goal.
Do I need a heart rate monitor to use these zones?
To train by them accurately, yes — a chest strap or wrist monitor lets you keep your heart rate within the target range during exercise. Without one, you can approximate effort using perceived exertion, but a monitor is far more precise.
