Target Heart Rate Calculator
Calculate your personalized training heart rate zones (50-85%) using the Karvonen formula based on your age and resting pulse.
Example
For a 30-year-old with a resting heart rate of 60 bpm:
Max HR = 220 - 30 = 190 bpm
Heart rate reserve = 190 - 60 = 130 bpm
Karvonen target = (reserve x intensity) + resting
50% zone = (130 x 0.50) + 60 = 125 bpm
70% zone = (130 x 0.70) + 60 = 151 bpm
85% zone = (130 x 0.85) + 60 = 171 bpm
Recommended training zone: 151 - 171 bpm
How it works
Maximum heart rate is estimated as 220 minus your age, then the Karvonen formula applies your chosen intensity to your heart rate reserve: target = ((maxHR - resting) x intensity) + resting. Zones from 50% to 85% are shown for warm-up through peak effort.
Good to know
This Target Heart Rate Calculator turns two numbers you already know — your age and your resting pulse — into five practical training zones, from a gentle warm-up at 50% all the way up to a peak effort at 85%. Instead of a single "fat burn" number, it uses the Karvonen heart-rate-reserve method, which subtracts your resting heart rate before applying intensity, so the targets reflect how fit you actually are rather than a generic age-only estimate. It is built for runners, cyclists, gym-goers, and anyone using a chest strap or wrist monitor who wants to train by pulse rather than guesswork.
Reach for it when you are planning a workout structure: easy recovery days near the warm-up and fat-burn zones, steady cardio in the aerobic 70% band, and hard intervals pushing into the anaerobic and peak bands. The highlighted "recommended training zone" (70–85% reserve) is the range most general fitness guidance points to for building cardiovascular endurance, so it is a reasonable default if you just want one band to aim for.
To read the result, find your goal intensity, then keep your monitored heart rate inside that bpm window during the working part of your session. Because each zone is a single rounded number, treat it as the center of a band rather than a hard line — drifting a few beats either side is normal. The badge also reports your estimated maximum heart rate (220 minus age) so you can sanity-check the zones; if your resting rate is entered higher than that maximum, no zones can be produced.
One practical caveat: the accuracy of every zone depends on two estimates — the 220-minus-age maximum and a true resting heart rate. Measure your resting pulse first thing in the morning before getting out of bed for the most reliable input, and remember that caffeine, heat, stress, dehydration, and some medications can push your live heart rate well above the predicted zone even at an easy effort.
Frequently asked questions
Why use resting heart rate (the Karvonen method) instead of just a percentage of max HR?
The Karvonen method bases zones on your heart rate reserve (max HR minus resting HR), which accounts for your individual fitness. A fitter person with a lower resting heart rate gets more personalized targets than the simpler percentage-of-max-HR approach.
How accurate is the 220-minus-age formula for maximum heart rate?
It is a popular estimate but can be off by 10-12 bpm for many people. For precise zones, an exercise stress test or field test of your true maximum heart rate is more reliable, especially for athletes or older adults.
Is my data uploaded anywhere?
No — this calculator runs entirely in your browser; nothing is uploaded.
Is this a substitute for medical advice?
No. These are educational estimates — consult a qualified health professional for medical decisions.
People also ask
How do I measure my resting heart rate correctly?
Take your pulse right after you wake up, before getting out of bed or having caffeine, and count beats for a full 60 seconds (or use a wearable's overnight resting figure). Averaging several mornings gives a more stable number than a single reading.
What is a normal resting heart rate for adults?
For most adults a resting heart rate falls roughly between 60 and 100 beats per minute, and trained endurance athletes are often lower, sometimes 40 to 60. A rate that is consistently very high or very low is worth discussing with a clinician.
Which heart rate zone is best for losing weight?
Lower-intensity zones burn a higher percentage of calories from fat, but higher-intensity work burns more total calories per minute. Overall weight change depends on total energy balance over time rather than on one specific zone.
What does heart rate reserve actually mean?
Heart rate reserve is your estimated maximum heart rate minus your resting heart rate, representing the range your heart can ramp up across. The Karvonen method applies a chosen intensity percentage to this reserve and then adds your resting rate back.
Why is my smartwatch heart rate different from these zones?
Optical wrist sensors can read inaccurately during fast or high-intensity movement, and the calculator's zones rely on an estimated maximum heart rate that may not match yours. A chest-strap monitor and a measured maximum generally produce closer agreement.
Should beginners train in the higher 70 to 85 percent zone?
People new to exercise often start with more time in the warm-up and aerobic ranges and build toward harder efforts gradually. Anyone with a heart condition, who is pregnant, or who is returning from inactivity should check with a health professional before targeting high-intensity zones.
Are there more accurate maximum heart rate formulas than 220 minus age?
Alternative equations such as 208 minus 0.7 times age have been proposed and may fit some populations better, but all age-based formulas are estimates. A supervised exercise stress test or a field max-effort test gives the most individualized value.
Related calculators