The Target Heart Rate Calculator estimates the ideal heart rate zones for exercise, based on your maximum heart rate. Provide your age (or a tested maximum heart rate) and, optionally, your resting heart rate.
The target heart rate calculator tells you the heart rate zones to aim for during exercise so you can train at the right intensity for your goals. It starts from your maximum heart rate — estimated from your age or entered from a fitness test — and, using your resting heart rate, calculates personalized target zones with the well-established Karvonen method. It also offers perceived-exertion scales for those who prefer to gauge effort by feel. Whether you are trying to burn fat, build endurance, or push your peak fitness, exercising in the correct heart rate zone makes your training more effective and safer.
Heart rate is one of the best real-time signals of how hard your body is working. Too easy, and you may not be getting the benefit you want; too hard, and you risk burnout or injury. Knowing your target zones takes the guesswork out of intensity and lets you match your effort to your objective.
Your target heart rate is the range of heartbeats per minute (bpm) at which you should aim to exercise to achieve a specific training effect. It is expressed as a percentage of your capacity and translated into actual bpm figures. Rather than a single number, it is really a set of zones — lighter zones for warm-up and recovery, moderate zones for endurance and fat metabolism, and harder zones for building peak cardiovascular fitness.
Training within these zones ensures your effort is neither wasted nor excessive. It is the foundation of structured cardio training used by everyone from casual exercisers to elite athletes.
Everything starts with your maximum heart rate (MHR) — the highest number of times your heart can beat per minute during all-out effort. The most accurate way to know it is a supervised maximal exercise test, and if you have one, you can enter that value directly. For most people, though, MHR is estimated from age using one of several formulas. This calculator offers three:
All age-based formulas are population averages — an individual's true maximum can differ by 10 to 20 bpm — so treat the estimate as a useful starting point rather than an exact figure.
The most personalized method this calculator uses is the Karvonen formula, which is based on your heart rate reserve (HRR) rather than just your maximum heart rate. Heart rate reserve is the difference between your maximum and resting heart rates — the "room" your heart has to work in. The formula is:
Target HR = ((Max HR − Resting HR) × Intensity%) + Resting HR
By factoring in your resting heart rate, the Karvonen method tailors the zones to your individual fitness. A fitter person with a lower resting heart rate gets different, more accurate targets than a simple percentage of maximum would give. For example, a 30-year-old with a max HR of 190 and a resting HR of 70 has a heart rate reserve of 120. Exercising at 50% intensity gives a target of (120 × 0.5) + 70 = 130 bpm; at 85%, (120 × 0.85) + 70 = 172 bpm. So this person's aerobic training zone runs from about 130 to 172 bpm.
If you do not enter a resting heart rate, the calculator falls back to expressing the zones as straightforward percentages of your maximum heart rate.
The calculator divides effort into five zones, each serving a different training purpose:
Not everyone wants to monitor a heart rate number while exercising. The calculator also offers two perceived-exertion scales that let you gauge intensity by how hard the effort feels, then maps each level to a target heart rate using your heart rate reserve. The Borg RPE scale (6–20) runs from "no exertion" up to "maximal exertion," with the numbers loosely corresponding to heart rate in older adults. The Borg CR10 scale (0–10) is a simpler category-ratio version. Both are valuable because your perceived effort automatically accounts for factors a formula cannot — heat, fatigue, illness, or a bad night's sleep — making them a robust everyday guide to training intensity.
Choose whether to estimate your maximum heart rate from your age or to enter a tested value. If estimating from age, pick which formula to use. Enter your resting heart rate if you know it — measuring it first thing in the morning before getting up gives the most accurate reading — for personalized Karvonen zones. Select the intensity scale you prefer, then click Calculate to see your target heart rate zones.
Matching intensity to purpose is what separates effective training from aimless effort. If your goal is endurance, spending time in the moderate aerobic zone builds the cardiovascular base you need. If you want to improve speed and power, targeted work in the harder zones raises your ceiling. Even fat loss benefits from zone awareness: while the lighter zones burn a higher proportion of fat, higher-intensity work burns more total calories, and a well-designed program uses a mix. Heart rate zones give you an objective way to structure that mix, track your progress as your fitness improves (you will be able to do more work at the same heart rate), and avoid the common trap of always training too hard or too easy.
To use these zones during exercise, you need to measure your heart rate. A chest-strap monitor or a wrist-based fitness watch gives continuous, convenient readings. You can also check manually: place two fingers on your wrist or neck, count the beats for 15 seconds, and multiply by four. For resting heart rate, measure when you are calm and rested, ideally right after waking, before caffeine or activity. A typical adult resting heart rate is 60–100 bpm, and well-conditioned athletes are often well below that.
Different fitness goals call for time spent in different heart rate zones, and knowing your targets lets you train with purpose rather than guesswork:
A well-rounded program mixes these zones. A popular approach among endurance athletes is to spend the large majority of training time at easy-to-moderate intensities and only a small fraction at high intensity — an 80/20 split that builds fitness while limiting injury and burnout.
Your heart rate at any moment reflects more than just exercise intensity. Several factors can raise or lower it, which is worth keeping in mind when interpreting the numbers. Heat and humidity push heart rate up as the body works to cool itself. Dehydration has a similar effect. Caffeine and certain medications can raise it, while some medications — notably beta-blockers — deliberately lower it, which makes standard target zones inaccurate for people taking them. Stress, illness, and poor sleep all elevate heart rate, and altitude raises it too. Fitness level matters as well: as you get fitter, your heart becomes more efficient, so your resting heart rate falls and you can do more work at any given heart rate. This is exactly why recalculating your zones periodically, and using a recent resting heart rate, keeps your training targets accurate.
Beyond its role in the Karvonen formula, your resting heart rate is a valuable health and fitness indicator in its own right. A lower resting heart rate generally reflects a stronger, more efficient heart that pumps more blood with each beat. As you become fitter through regular cardio training, your resting heart rate typically drops — endurance athletes often have resting rates in the 40s or even 30s, well below the typical adult range of 60 to 100 beats per minute. Tracking your resting heart rate over weeks and months is therefore a simple, free way to watch your fitness improve, and an unusually elevated morning reading can be an early sign of overtraining, illness, dehydration, or poor sleep. For the most consistent measurement, check it at the same time each day, ideally right after waking and before getting out of bed.
Heart rate training is a valuable tool, but the estimated maximum heart rate is a population average, and your true maximum may be higher or lower. Never treat a calculated maximum as a hard limit to chase. Listen to your body, build intensity gradually, and stop if you feel dizzy, unusually short of breath, or experience chest discomfort. If you are new to exercise, older, pregnant, or have any cardiovascular condition or take medication that affects heart rate, talk to your doctor before using heart rate zones to guide training. Used sensibly, these zones make exercise more effective; used rigidly, they can push you harder than is wise.
For general fitness, moderate exercise at roughly 50–70% of your capacity is recommended, moving into 70–85% for more vigorous training. The exact bpm depends on your maximum and resting heart rates, which is what this calculator works out for you.
The Tanaka formula (208 − 0.7 × age) is generally considered more accurate across ages than the classic 220 − age. All age-based estimates are averages, though — a supervised test is the only way to know your true maximum.
Heart rate reserve (HRR) is your maximum heart rate minus your resting heart rate. The Karvonen formula uses it to personalize your zones, which makes the targets more accurate than a plain percentage of maximum heart rate.
It is optional but recommended. With it, the calculator uses the Karvonen method for personalized zones. Without it, the zones are shown as simple percentages of your maximum heart rate.
Lower-intensity exercise burns a higher proportion of calories from fat, but higher-intensity exercise burns more total calories in the same time. For weight loss, total calories burned and overall energy balance matter most, so a mix of zones combined with good nutrition is most effective.
Rating of Perceived Exertion is a way of measuring how hard exercise feels on a numbered scale. The Borg 6–20 and CR10 scales let you judge intensity by feel, which automatically accounts for factors like heat, fatigue, and stress that a heart rate formula cannot.
This Target Heart Rate Calculator is provided for educational and general informational purposes and uses population-average formulas. Individual maximum heart rates vary, and these zones are estimates. Consult a doctor before beginning a new exercise program, especially if you have any heart condition, take medication that affects heart rate, or have been inactive.