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Target Heart Rate Calculator

Target heart rate turns an intensity you can name into a pulse you can check. The arithmetic is short; the interesting part is that almost every input is an estimate.

Target heart rate

151

Estimated maximum heart rate
190
Heart rate reserve
130
Bottom of the aerobic band (50 per cent)
125
Top of the aerobic band (85 per cent)
170.5

Values update as you type. This calculator covers the single scenario its formula assumes — see Common Mistakes for what it leaves out.

The formula this calculator uses

Target HR = Resting HR + (Max HR - Resting HR) x Intensity

HRrest
Resting heart rate, taken before getting out of bed
HRmax
Estimated maximum heart rate, usually 220 minus age
reserve
Heart rate reserve, equal to HRmax minus HRrest
intensity
Share of the reserve, written as a decimal
target
Target heart rate in beats per minute

How to check the result by hand

  1. 1

    Measure the resting heart rate properly

    Take the pulse for a full minute while still lying in bed, before coffee or movement. A rate taken after climbing stairs is not a resting rate, and using one inflates the reserve and shifts every later figure. Averaging several mornings gives a more stable number than any single reading.

  2. 2

    Estimate the maximum from age

    220 minus age gives a working figure; the Tanaka version, 208 minus 0.7 times age, gives another. They disagree, so record which one you used, because the choice moves the final target.

  3. 3

    Subtract resting from maximum to get the reserve

    For 30 years and a resting rate of 60 the estimate is 190 and the reserve is 190 - 60 = 130. This reserve, not the maximum, is what the intensity percentage applies to.

  4. 4

    Apply the intensity to the reserve and add it back

    Seventy per cent of 130 is 91, and 60 + 91 = 151. Adding the resting rate back is what distinguishes Karvonen from a plain percentage of the maximum.

  5. 5

    Compare with the band and sanity-check

    The same reserve gives 125 at 50 per cent and 170.5 at 85 per cent, so a target of 151 sits comfortably inside the moderate range. If a figure falls outside the band, recheck the units before trusting it. Bands are more forgiving than a single point, which is precisely why they are quoted as ranges.

For worked examples, common mistakes and the limits of this formula, read the full How To Calculate Target Heart Rate page.