Fitness · 5 min read
How to Calculate Heart Rate Training Zones
220 − age, five bands — and why the estimate is not a diagnosis
Heart-rate training zones are fractions of an estimated maximum, often 220 minus age. This tutorial walks through that estimate, five intensity bands, and the optional Karvonen formula when a resting heart rate is entered. The numbers are a coarse training sketch, not medical advice and not a diagnosis of fitness or risk.
Written by the My Calculator Stack editorial team. About our methods
This is not medical advice, not a diagnosis, and not a clearance to exercise. Maximum heart rate from 220 − age is a population estimate that can miss an individual by a wide margin. Karvonen zones still depend on that estimate. Do not use these bands to interpret chest pain, dizziness, or an irregular pulse. Talk to a qualified clinician before starting or changing an exercise program.
1.What heart-rate zones are
Training zones divide intensity into bands so easy work and hard work stay distinct. Many consumer charts use percentages of estimated maximum heart rate. They are not a VO₂ test, not a lactate threshold, and not a medical assessment. Age-predicted max can be high or low for a given person. Treat the bands as a teaching scale, then talk to a clinician if you need exercise clearance.
2.The formula
A common estimate is HR_max ≈ 220 − age (years). Five bands as percent of that max: zone 1 50–60%, zone 2 60–70%, zone 3 70–80%, zone 4 80–90%, zone 5 90–100%. If a resting heart rate HR_rest is entered, Karvonen uses heart-rate reserve: target = HR_rest + (HR_max − HR_rest) × intensity. Leave rest blank to stay on percent-of-max. Other max-HR formulas exist; 220 − age is the estimate used here because it is widely taught, not because it is individually accurate.
\[ \begin{aligned}\mathrm{HR}_{\max} &\approx 220 - a \\\mathrm{HR} &= \mathrm{HR}_{\mathrm{rest}} + (\mathrm{HR}_{\max}-\mathrm{HR}_{\mathrm{rest}})\times i\end{aligned} \]
3.Worked example
Take age 30. Estimated max = 220 − 30 = 190 bpm. Percent-of-max bands: zone 1 95–114, zone 2 114–133, zone 3 133–152, zone 4 152–171, zone 5 171–190 bpm (rounding to whole beats). If resting heart rate is 60 bpm, Karvonen reserve is 130. Zone 2 (60–70% of reserve) is then 60 + 0.60×130 = 138 through 60 + 0.70×130 = 151 bpm — different from percent-of-max zone 2. Both sketches are approximate, not a diagnosis.
\[ \mathrm{HR}_{\max}=220-30=190 \]
4.Zone-band playground
Move age to shift estimated max and the five bands. Optionally enter a resting heart rate to switch the scale to Karvonen; leave it empty to keep percent of max. This is a teaching widget — no favorites, no full calculator chrome. There may be no dedicated zones tool on the calorie page; use the TDEE and BMR tutorials for energy estimates, then browse fitness calculators for related screening tools.
Inline playground
Percent of estimated max
0 or blank = percent of 220 − age. Above 0 uses Karvonen.
Estimated max HR
190 bpm
220 − 30 = 190
Screening aid only — not medical advice, not a diagnosis. 220 − age can miss an individual by a wide margin. Do not use these bands to interpret symptoms.
5.Where to go next
Heart-rate bands do not set calorie intake. Open How to Calculate Daily Calories (TDEE) or How to Calculate BMR if you need energy estimates, then browse fitness calculators for BMI, pace, and related tools. Treat every zone as a sketch, not medical advice.
Try it yourself
Open the related calculator and put these formulas to work.