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    Target Heart Rate Calculator

    Calculate your personalised target heart rate zone for exercise using the Karvonen or percentage method. Optimise fat burn, cardio fitness, or peak performance.

    Free to use. Runs in your browser.

    Enter your age and resting heart rate to calculate training zones. Zone 2 (60 to 70% of max) builds aerobic base. Zone 4 (80 to 90%) improves anaerobic threshold.

    Calculate Target Heart Rate

    Why Exercising by Heart Rate Changes Everything

    Most people have two exercise speeds: too easy or too hard. They walk for an hour and wonder why nothing changes, or they sprint until they can't breathe and quit after two weeks. The sweet spot, the intensity that actually produces results, requires precision. That's what target heart rate gives you.

    Your target heart rate is the range where exercise is intense enough to trigger adaptation but sustainable enough to maintain for the duration of your workout. Think of it like the rev range in a car, too low and you're wasting fuel going nowhere, too high and you'll blow the engine.

    The right target zone depends on your goal. Fat loss, cardiovascular fitness, and race performance all happen at different intensities. Training in the wrong zone isn't dangerous, but it's inefficient, and most people don't have unlimited time to exercise.

    Target Heart Rate by Fitness Goal

    These ranges use percentage of heart rate reserve (Karvonen method) for greater accuracy. Your actual bpm targets depend on your age and resting heart rate, use the calculator above to find yours.

    Goal% Heart Rate ReserveSession DurationWeekly Frequency
    Weight loss (beginner)40 to 60%30 to 60 min3 to 5 days
    Fat burning (experienced)60 to 70%45 to 90 min4 to 6 days
    General fitness60 to 80%30 to 60 min3 to 5 days
    Race training70 to 85%20 to 60 min3 to 4 days
    Peak performance85 to 95%Intervals: 2 to 5 min1 to 2 days

    What this means for you: If you're exercising for general health and fitness, the 60 to 80% range covers most of what you need. Spend 80% of your training at the lower end and 20% at the higher end. This "polarised" approach, endorsed by sports science and used by elite endurance athletes, produces better results than training at a moderate intensity every session.

    Resting Heart Rate: Your Hidden Fitness Score

    Your resting heart rate isn't just a number for the Karvonen formula, it's one of the most reliable indicators of cardiovascular health. A lower resting HR means your heart pumps more blood per beat, so it doesn't need to work as hard at rest.

    Resting HR (bpm)Fitness LevelWhat It Means
    <50AthleteHighly trained cardiovascular system
    50 to 60ExcellentVery fit, regular exerciser
    60 to 70GoodAbove average fitness
    70 to 80AverageTypical for sedentary adults
    80 to 100Below averageCould improve with regular exercise
    >100See a doctorMay indicate an underlying condition

    How to measure it: Take your pulse first thing in the morning, before getting out of bed, on 3 consecutive days. Average the results. Don't measure after caffeine, alcohol, or a poor night's sleep, these artificially elevate your reading.

    Max Heart Rate: Why 220 Minus Age Is Wrong

    The "220 minus age" formula was never based on original research, it was derived from a rough estimate in the 1970s that got repeated until everyone assumed it was fact. It can be off by 10 to 20 bpm in either direction. For a 40-year-old, that's the difference between a max of 160 and 180, which changes every zone dramatically.

    This calculator uses the Tanaka formula (208 − 0.7 x age), published in the Journal of the American College of Cardiology in 2001. It's more accurate across all age groups, though still an estimate. The only way to know your true max HR is a graded exercise test, either supervised by a cardiologist or as a field test (see our Heart Rate Zone Calculator for the protocol).

    If you own a heart rate monitor and regularly push yourself during exercise, your highest recorded heart rate during an all-out effort is likely close to your true max. Use the "Custom Max HR" field above to enter a known value.

    Common Mistakes When Using Heart Rate Targets

    Using the Wrong Max HR

    The 220 − age formula can be off by 10 to 20 bpm. If possible, use the Tanaka formula or a field test. Wrong max HR means wrong zones, and wrong zones mean wasted training.

    Ignoring Resting HR Changes

    As you get fitter, your resting HR drops, which changes your Karvonen zones. Retest every 4 to 6 weeks. An athlete with a resting HR of 50 has very different zones than a beginner at 80 bpm.

    Training Too Hard, Too Often

    Going all-out every session feels productive but leads to overtraining, fatigue, and injury. The 80/20 rule: 80% of sessions at conversational pace (Zones 1 to 2), 20% at high intensity (Zones 4 to 5).

    Not Accounting for External Factors

    Heat, humidity, caffeine, stress, sleep, and dehydration all raise heart rate at a given effort level. If your HR seems high relative to effort, it's a sign to back off, not push harder.

    Related Fitness Tools

    Heart Rate ZonesSee all 5 training zonesVO2 Max CalculatorEstimate your aerobic fitnessPace CalculatorCalculate your running paceCalories BurnedSee how activities compareBMI CalculatorCheck your body mass indexTDEE CalculatorFind your daily calorie needs

    How to use this tool

    1

    Enter your age

    2

    Enter your resting heart rate (optional but recommended)

    3

    Choose the calculation method

    Common uses

    • Finding your ideal exercise intensity for fat loss
    • Setting heart rate targets for cardio training
    • Monitoring workout intensity with a heart rate monitor
    • Adjusting training zones as fitness improves
    • Comparing Karvonen and percentage calculation methods

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    Frequently Asked Questions

    What is target heart rate?
    Target heart rate is the ideal bpm range for your specific exercise goal. Fat burning happens at 50 to 70% of your heart rate reserve, cardiovascular fitness at 70 to 85%, and peak performance at 85 to 95%. Your exact targets depend on age and resting heart rate.
    How is max heart rate calculated?
    This calculator uses the Tanaka formula: 208 − (0.7 x age), published in 2001 and more accurate than the older 220 − age formula. For a 40-year-old, Tanaka gives 180 bpm vs 220-age giving 180, they converge at 40 but diverge at other ages. You can also enter a known max HR.
    What is the Karvonen method?
    The Karvonen formula uses your heart rate reserve (max HR minus resting HR) for personalised zones: Target = ((Max HR − Resting HR) × %) + Resting HR. It's significantly more accurate than the simple percentage method because it accounts for your individual fitness level.
    What heart rate zone should I exercise in?
    For fat loss: 50 to 70% of heart rate reserve (conversational pace). For cardiovascular fitness: 70 to 85% (can speak only in short sentences). For peak performance: 85 to 95% (intervals only). Most people benefit from spending 80% of training time in lower zones and 20% in higher zones.
    How do I measure my resting heart rate?
    Measure your pulse first thing in the morning before getting out of bed, on 3 consecutive days, and average the results. Count beats for 60 seconds for accuracy. Don't measure after caffeine, alcohol, or a bad night's sleep, these inflate the number.
    Is the 220-minus-age formula accurate?
    No. It was never based on original research, it came from a rough estimate in the 1970s that got repeated until everyone assumed it was fact. It can be off by 10 to 20 bpm. The Tanaka formula (208 − 0.7 x age) is better, but the only reliable way to find your true max HR is a field test or supervised stress test.
    What is a good resting heart rate?
    For adults: under 60 bpm is excellent, 60 to 70 is good, 70 to 80 is average, 80 to 100 is below average. Elite endurance athletes can have resting HRs in the 30s to 40s. A consistently elevated resting HR (above 100 bpm) may indicate a medical condition and warrants a doctor's visit.
    Should I ever exercise at my max heart rate?
    Briefly, yes, during short intervals (30 seconds to 3 minutes). This trains your VO2 max and anaerobic capacity. But you shouldn't sustain max effort for more than a few minutes, and these sessions should only happen 1 to 2 times per week with full recovery between them.
    How does fitness level affect my target heart rate?
    As you get fitter, your resting HR drops and your heart rate reserve increases. This means your Karvonen zones shift, the same percentage effort corresponds to a higher bpm. Retest your resting HR every 4 to 6 weeks and update your targets. The percentage method doesn't capture this change.
    Can medications change my target heart rate?
    Yes. Beta-blockers lower both resting and maximum heart rate, making standard formulas inaccurate. Stimulant medications, decongestants, and some antidepressants can raise resting HR. If you take any heart-affecting medication, consult your doctor for personalised training zones.
    What heart rate zone burns the most fat?
    Zone 2 (60 to 70%) burns the highest percentage of calories from fat. However, higher zones burn more total calories per minute. For weight loss, total calorie deficit matters more than the fat-burning zone. That said, Zone 2 training builds the aerobic base that makes all other training more effective.
    How do I know if I'm training too hard?
    Signs of overtraining include: elevated resting heart rate (5 to 10 bpm above normal), persistent fatigue that doesn't improve with rest, decreased performance despite more training, frequent illness, mood changes, and disturbed sleep. If your resting HR is elevated for more than 3 days, take a recovery week.

    Results are for general informational purposes only and should be checked before use. They are not professional advice. See our Disclaimer and Terms of Service.