Heart Rate Zone Calculator
Free heart rate zone calculator. Enter your age and resting heart rate to get your max HR and five training zones using the Karvonen formula. For cardio and fat-burn training.
Uses the Karvonen formula: target HR = (max HR − resting HR) × intensity + resting HR, with max HR estimated as 220 − age.
About This Free Online Heart Rate Zone Calculator
Our free heart rate zone calculator works out your five training zones from your age and resting heart rate. It estimates your maximum heart rate as 220 minus age, then applies the Karvonen formula — target HR = (max HR − resting HR) × intensity + resting HR — to give the bpm range for each zone: very light recovery, light fat burn, moderate aerobic, hard anaerobic, and maximum VO2. Whether you train with a chest strap or a wrist monitor, knowing your zones keeps easy days easy and hard days hard. Everything runs in your browser — instant, private, no signup.
Features of Our Heart Rate Zone Calculator
- Five zones from age and resting HR
- Uses the accurate Karvonen formula
- Shows max, fat-burn and cardio ranges
- bpm ranges for every intensity
- 100% client-side and private — instant results, no signup
How to Use the Heart Rate Zone Calculator
Using this tool is simple and requires no signup or registration. Follow these steps:
- Enter your age.
- Enter your resting heart rate (bpm).
- Read your max heart rate.
- Use the zone ranges to guide training.
Frequently Asked Questions About Heart Rate Zone Calculator
What is the Karvonen formula?
The Karvonen formula sets your target heart rate as (max HR − resting HR) × intensity + resting HR. Because it factors in your resting heart rate, it personalises each zone better than a simple percentage of max HR alone.
How is maximum heart rate estimated?
The common estimate is 220 minus your age. It is a rough population average — your true max can vary by 10–15 bpm — but it works well for setting training zones.
Which zone burns the most fat?
Zone 2 (about 60–70% of reserve) is called the fat-burn zone because a higher share of the energy comes from fat, though total calories matter most for weight loss. Zone 2 is also where you build aerobic base.
How do I find my resting heart rate?
Measure it first thing in the morning before getting out of bed: count pulses for 60 seconds, or use a fitness tracker’s overnight reading. Most adults sit between 60 and 100 bpm; trained athletes are often lower.
Is this heart rate zone calculator free?
Yes, completely free with no signup. All maths runs in your browser — nothing is uploaded or tracked.
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