Very light intensity. Warm-up, cool-down, and active recovery.
Zone 2 - Fat Burn
114 - 133 BPM
60%
70%
Light intensity. Burns fat as primary fuel. Long, easy workouts.
Zone 3 - Cardio
133 - 152 BPM
70%
80%
Moderate intensity. Improves cardiovascular fitness and endurance.
Zone 4 - Threshold
152 - 171 BPM
80%
90%
Hard intensity. Increases speed and lactate threshold.
Zone 5 - Maximum
171 - 190 BPM
90%
100%
Maximum effort. Short bursts only. Improves maximum performance.
Zone Overview
95-114
114-133
133-152
152-171
171-190
Max Heart Rate Formula
Max HR: 220 - Age = 220 - 30 = 190
The most common formula for estimating maximum heart rate is 220 minus your age. While not perfectly accurate for everyone, it provides a good baseline for training zones.
What is a Heart Rate Calculator?
A heart rate calculator estimates your maximum heart rate from your age and breaks it into five training zones, from light fat-burning effort all the way up to maximal anaerobic work. During aerobic exercise such as running, cycling, or brisk walking, your heart rate is an objective number that tells you how hard you are actually working, so you can match your intensity to your goal: easy weight-management sessions, building endurance, or sharpening race speed. With wrist-based smartwatches and chest-strap monitors now widespread, zone displays appear in most fitness apps and gym equipment. This tool gives the quick age-based estimate and also explains the Karvonen method, which uses your resting heart rate for a more personalized target, helping you find the zone that fits you.
How to Use
1. Enter your age.
2. Calculate to see your estimated maximum heart rate and five training zones (each shown as a low-to-high range in beats per minute).
3. Pick the zone that matches your goal: around zone 2 for easy fat-burning effort, the moderate zones 3-4 for building endurance.
4. While exercising, adjust your pace so your monitor stays within the target zone.
Formula & Definition
The simplest estimate is:
Maximum heart rate = 220 - age
So a 40-year-old has a max of about 180 bpm. Each zone is a percentage band of that maximum (zone 1 = 50-60%, zone 2 = 60-70%, zone 3 = 70-80%, zone 4 = 80-90%, zone 5 = 90-100%). The Karvonen method captures individual fitness better by working from your heart rate reserve (max minus resting):
Target HR = (max HR - resting HR) x intensity% + resting HR
This reflects differences in fitness between two people of the same age.
Interpreting Results
Zones 1-2 are easy enough to hold a conversation and suit warm-ups and steady fat-burning effort. Zone 3 is a moderate effort that builds cardiovascular fitness, while zones 4-5 are hard, breathless intensities that develop speed and peak endurance but cannot be sustained for long. Remember that '220 - age' is a population average; an individual's true maximum can vary by roughly 10-12 bpm. Readings are also affected by monitor accuracy, caffeine, poor sleep, and heat, so treat the numbers as a guide rather than an exact limit. Stop exercising immediately if you feel chest pain, dizziness, or unusual breathlessness.
Frequently Asked Questions
How accurate is '220 - age' for max heart rate? ▾
It is a population average and can be off by about 10-12 bpm for any individual. For a precise figure you would need a supervised exercise stress test.
Which zone is best for burning fat? ▾
Fat supplies most of the energy at roughly 60-70% of maximum (around zone 2). However, higher-intensity work burns more total calories, so choose based on your goal.
How is the Karvonen method different? ▾
It factors in your resting heart rate, so two people of the same age with different fitness get different targets. Measure resting heart rate first thing in the morning.
Can I use this if I take medication? ▾
Some medicines such as beta-blockers lower heart rate, so age-based estimates may not apply. If you are on medication, ask your doctor about a suitable intensity.
This tool provides a general age-based estimate and is not medical advice or a diagnosis. If you have heart disease, high blood pressure, take medication, or are unsure about exercising, consult a doctor before starting.