Target Heart Rate Calculator
Calculate your target heart rate range for exercise based on age and fitness goals.
Target Heart Rate for Exercise
The American Heart Association recommends exercising at 50-85% of your maximum heart rate. For moderate exercise, aim for 60-70%; for vigorous exercise, 70-85%. The 10-second pulse count lets you quickly check your heart rate mid-workout by counting beats for 10 seconds.
About This Tool
Picking the right heart rate zone for a workout is harder when the formulas you've heard are all different — 220 minus your age is famously imprecise.
Enter your age (and optionally resting heart rate) and the calculator returns target zones for warm-up, fat-burn, cardio, and peak intensity. Two methods are offered: the simple 220-age method, and the Karvonen method which uses heart rate reserve (max minus resting) and gives more accurate zones for people whose resting HR isn't average.
The Tanaka formula (208 - 0.7 × age) is more accurate than 220-age for older adults and is offered as an alternative. Differences between formulas are 5–10 bpm at the extremes — not huge, but enough to matter if you're pacing carefully on a long run. The most accurate way to find your max is a supervised treadmill test, which is what athletes actually do.
The formulas estimate maximum heart rate from age. 220 − age is the original (1971), based on a small sample, but stuck in popular use because it's memorable. Tanaka (208 − 0.7 × age) was published in 2001 from a meta-analysis of 351 studies and is more accurate, especially for adults over 40. Gulati (206 − 0.88 × age) was developed specifically for women in 2010. The Karvonen method computes target heart rate as: HRmax − HRrest) × intensity + HRrest, using the heart rate reserve (HRR) — the difference between max and resting HR.
The pain this addresses: heart rate training without a clinical max-effort test. Without knowing your actual HRmax, you're using a formula estimate that can be off by 10-20 bpm. That sounds small but matters for zone training: zone 2 (aerobic base building) is typically 60-70% of HRmax. If your true max is 180 but the formula says 190, your zone 2 ceiling shifts from 126 to 133 bpm. Train at 133 thinking it's zone 2, you're actually in zone 3 (tempo), which produces different adaptations and more fatigue.
Worked example: 40-year-old, resting HR 60. 220-age formula gives HRmax = 180. Tanaka gives HRmax = 180 too at this age (208 − 28 = 180), one of the convergence points. Karvonen for 70% intensity: (180 − 60) × 0.70 + 60 = 144 bpm. Compare to a simple 70% of HRmax: 0.70 × 180 = 126 bpm. The Karvonen number is higher because it accounts for the resting HR floor that you can't go below. For someone with low resting HR (athletes), this difference is large; for someone with high resting HR (sedentary or stressed), it's smaller.
Where this is unreliable: medications and conditions. Beta-blockers cap heart rate response significantly — somebody on metoprolol might have an effective HRmax 30 bpm below the formula prediction. Pregnancy, heat, dehydration, and stimulant use all shift heart rate at a given workload. Heart conditions (atrial fibrillation, ventricular tachycardia) can produce heart rates that don't correlate with workload at all. The formula is for healthy adults without confounding factors. If any apply, work with a clinician rather than trusting the math.
The about text and FAQ on this page were drafted with AI assistance and reviewed by a member of the Coherence Daddy team before publishing. See our Content Policy for editorial standards.