Target Heart Rate Calculator

How this target heart rate calculator works

This page estimates a training heart rate for healthy adults and keeps the related questions on one screen. Enter age, an optional resting heart rate, and an ACSM intensity preset. The result updates as you type. Leave resting heart rate blank when you want a percent of maximum heart rate. Enter it when you want the Karvonen heart-rate reserve method. If you already know a measured maximum, enter that value and the age equation steps aside. Maximum heart rate, the ACSM intensity table, and a zone 2 shorthand stay on this target heart rate calculator. There is no separate max heart rate page and no separate heart rate zones page.

The primary result is the low and high end of the preset you select: light, moderate, or vigorous. Each beat total is rounded to the nearest whole number after the published percent is applied. The line under the result names the method and the percent band. The formula box shows the substituted arithmetic for the current inputs. Default moderate uses the full ACSM moderate band, not a single midpoint. A definitional check of the reserve method is age 40, resting heart rate 60 bpm, and Tanaka maximum 180 bpm. Fifty percent of heart-rate reserve is (180 − 60) × 0.50 + 60 = 120 bpm. The moderate range around that check is wider than one percent, because the ACSM moderate band is 40–59% of heart-rate reserve, which rounds to 108–131 bpm for those same inputs.

Maximum heart rate

Predicted maximum heart rate uses Tanaka, Monahan, and Seals (2001) by default:HRmax = 208 − (0.7 × age). Their meta-analysis of 351 studies supported that line for healthy adults. In the analyses they reported, the relationship did not depend on sex or on habitual physical activity. A separate laboratory check in the same paper was close to the same slope. This calculator uses the 208 − 0.7 × age form they recommended, and it labels the result as an estimate. Individual maximum heart rate still varies around the line.

The traditional alternative is HRmax = 220 − age, attributed to Fox, Naughton, and Haskell (1971). That classic line remains common in consumer tools and in teaching examples. It was not a regression fitted in a dedicated maximum-heart-rate study. Robergs and Landwehr (Journal of Exercise Physiology Online, 2002) describe it as an approximate line from pooled review material. Choose it when you want that older shortcut beside Tanaka. This page does not call 220 − age ACSM-validated. At age 40 the two equations both land on 180 bpm, so the definitional 120 bpm check is the same either way. At other ages they differ, and the result names which equation ran.

A measured maximum is more specific than either age equation when you already have one from a prior test you trust. Enter it in the maximum heart rate options and the page uses that number for the target range, the zone table, and the zone 2 shorthand. This calculator does not conduct a graded exercise test and does not invent a maximum from a workout file. Clearing the known-maximum field returns the estimate to the selected age equation.

Heart-rate reserve and percent of HRmax

When resting heart rate is present, target heart rate follows the Karvonen identity also used in ACSM’s Guidelines for Exercise Testing and Prescription:THR = [(HRmax − HRrest) × percent intensity] + HRrest. Heart-rate reserve is the gap between resting and maximum. The intensity percent applies to that gap, then resting heart rate is added back. Karvonen, Kentala, and Mustala (1957) expressed training intensity as a fraction of the range from rest to maximum. The form on this page is the rearrangement used in exercise-prescription teaching, including the ACSM heart-rate reserve method.

Without a resting value, the page uses the ACSM percent-of-maximum method:THR = HRmax × percent intensity. That method needs fewer inputs and matches the quick mode on many calculators. It is less individualized because two people with the same maximum and different resting rates receive the same beat target. Add a resting heart rate when you have a recent resting measurement and want the reserve method. Remove it when you want the simpler percent. The formula box switches with the inputs so the identity in use stays visible. Ranges use the low and high percents of the selected band. A single percent, such as the 50% check above, is the same identity evaluated at one point inside a band.

Heart-rate zones

The zone table uses ACSM relative-intensity bands from the Guidelines for Exercise Testing and Prescription, 10th edition (2018). Very light is under 30% of heart-rate reserve or under 57% of HRmax. Light is 30–39% of heart-rate reserve or 57–63% of HRmax. Moderate is 40–59% or 64–76%. Vigorous is 60–89% or 77–95%. Near-maximal effort is at least 90% of heart-rate reserve, or at least 96% of HRmax, through the maximum used on the page. Those cuts are the only zone boundaries in the calculator. They are not renamed Zone 1 through Zone 5, and they are not a coach-specific ladder.

When resting heart rate is filled in, every ACSM row uses the heart-rate reserve percents. When it is empty, every row uses the percent-of-HRmax column. The preset you select is marked in the table, and the primary result repeats that row’s beat range. Rounding to the nearest beat can make neighboring rows share a number or leave a one-beat gap. The percents stay on the ACSM cuts either way. An ACSM consumer tip sheet sometimes rounds moderate and vigorous differently for a short message. This calculator keeps the table above for the math and does not swap in those rounded marketing bands.

Zone 2 heart rate

Zone 2 is a consumer and endurance-training label. There is no single ACSM “Zone 2” coefficient, so this page does not invent one and does not present a proprietary five-zone system as science. The figure shown is the common shorthand of about 60–70% of HRmax, calculated from the same maximum as the rest of the page. Read it as a training alias that usually sits near ACSM light and the lower part of moderate. The comparison line under the shorthand repeats the ACSM light and moderate beat ranges for the current inputs.

Those expressions are not the same arithmetic. The shorthand always uses percent of maximum heart rate. The ACSM rows use heart-rate reserve when a resting heart rate is entered. A 60–70% HRmax band can overlap the lower portion of moderate on the reserve scale without matching it beat for beat. Use the ACSM rows when you want the published intensity classes. Use the shorthand when you want the label that endurance calculators often call zone 2. The caveat stays next to the number so the label is not mistaken for an ACSM zone.

Heart rate zones by age

Age changes this estimate by changing predicted maximum heart rate, unless you override that maximum. A higher age lowers both the Tanaka prediction and the 220 − age prediction, and every beat range moves with that maximum. Resting heart rate, when you enter it, shifts the reserve ranges again without changing the zone 2 shorthand’s percents of maximum. The table is an intensity estimate for healthy adults. It is not a chart of risk by age, and it is not a statement about what any person should sustain in a session.

Tanaka’s paper noted that 220 − age tends to underestimate maximum heart rate in older adults. That is one reason Tanaka is the default here. It is still an estimate. People of the same age do not share one maximum, which is why the known-maximum field exists. Repeat the same inputs when you compare one day with another. Change one field at a time when you want to see which assumption moved the range. Sex is not an input, because the Tanaka analyses this page relies on did not find a sex term to add.

Reading the estimate

Use the range as a planning estimate for the intensity you selected. It is not a measurement from a heart-rate strap, and it is not a diagnosis. Stop and seek care if you feel dizzy or have chest pain. A qualified fitness professional can help you decide how to use an estimate in training. This page does not adjust the math for drugs, and it does not offer clinical exercise targets.

Other EVR tools answer different questions. TheVO2 max calculator can use a measured maximum or the same Tanaka age equation inside a heart-rate ratio, but its output is aerobic capacity, not a target training range. The pace calculator converts distance and time. The calories burned calculator uses published MET values rather than heart-rate zones. None of those results should be pasted back into this page as if they were a maximum heart rate or a resting heart rate.

To estimate the calories a workout burned from your average heart rate, use the heart rate calorie calculator.

Sources

• Tanaka H, Monahan KD, Seals DR. Age-predicted maximal heart rate revisited. J Am Coll Cardiol. 2001;37(1):153-156. doi:10.1016/S0735-1097(00)01054-8. PMID 11153730.
• Fox SM III, Naughton JP, Haskell WL. Physical activity and the prevention of coronary heart disease. Ann Clin Res. 1971;3(6):404-432. PMID 4945367.
• Karvonen MJ, Kentala E, Mustala O. The effects of training on heart rate: a longitudinal study. Ann Med Exp Biol Fenn. 1957;35(3):307-315.
• American College of Sports Medicine. ACSM’s Guidelines for Exercise Testing and Prescription. 10th ed. Philadelphia: Wolters Kluwer; 2018. Relative intensity classification for percent heart-rate reserve (or percent VO2 reserve) and percent of maximum heart rate.
• Robergs RA, Landwehr R. Journal of Exercise Physiology Online. 2002. Cited here only to document the classic 220 − age equation’s origin, not as a different HRmax formula.

Frequently asked questions