Target Heart Rate Calculator
Find your training heart rate zones from max and resting heart rate.
About Target Heart Rate Calculator
The Karvonen method personalises training zones by factoring in your resting heart rate. A fitter person typically has a lower resting HR, which gives them a larger Heart Rate Reserve (HRR). Training at the same percentage of HRR therefore represents a higher absolute HR for the fit person — matching the actual physiological demand. The Tanaka formula for max HR is more accurate than the classic 220−age across ages 18–85, particularly for trained adults.
Formulas
Karvonen target heart rate
THR = (Max HR − Resting HR) × Intensity + Resting HR
- MHR
- Maximum heart rate (bpm)
- RHR
- Resting heart rate (bpm)
- I
- Training intensity as a decimal (e.g. 0.70 for 70%)
- THR
- Target heart rate (bpm)
Tanaka max HR
Max HR = 208 − 0.7 × Age
Worked example
With the default values below, Target Heart Rate Calculator returns Maximum Heart Rate of 190. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Ageaccepts 15–100 years
- 30 years
- Resting Heart Rateaccepts 30–120 bpm
- 65 bpm
- Max Heart Rate Methodone of 220 − Age (classic Fox formula), 208 − 0.7×Age (Tanaka et al. 2001 — more accurate for fit adults), Enter my own tested MHR
- 220 − Age (classic Fox formula)
- My Maximum Heart Rateaccepts 100–230 bpm
- 185 bpm
Results
- Maximum Heart Rate
- 190 bpm
- Heart Rate Reserve
- 125 bpm
- Zone 1 — Very Light50–60% HRR
- 128 bpm
- Zone 2 — Light60–70% HRR
- 140 bpm
- Zone 3 — Moderate70–80% HRR
- 153 bpm
- Zone 4 — Hard80–90% HRR
- 165 bpm
- Zone 5 — Maximum90–100% HRR
- 178 bpm
Step by step
- 1Maximum heart rate= 190 bpm
- 2Heart rate reserve= 125 bpm
- 3Zone 3 example (Karvonen at 70%)= 153 bpm
Assumptions and limits
- The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to whole numbers, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
- Heart rate zones are estimates. Maximum heart rate predictions carry ±10–12 bpm individual error. If you have a cardiovascular condition, consult your cardiologist before starting high-intensity exercise. Stop exercising and seek medical attention if you experience chest pain, dizziness or shortness of breath.
- This is an estimate for general information and not professional medical advice. See the full disclaimer for the limits that apply to this kind of calculator.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Heart rate zones are estimates. Maximum heart rate predictions carry ±10–12 bpm individual error. If you have a cardiovascular condition, consult your cardiologist before starting high-intensity exercise. Stop exercising and seek medical attention if you experience chest pain, dizziness or shortness of breath.
Frequently Asked Questions
How do I accurately measure my resting heart rate?
Measure immediately on waking, before getting out of bed, using a finger on your carotid or radial artery (or a wrist-based heart rate monitor). Count beats for 60 seconds. Average over 3 mornings. Stress, illness and alcohol elevate resting HR — measure on calm days.
What is the best zone for fat loss?
Zone 2 (60–70% HRR) uses the highest proportion of fat as fuel because intensity is low enough for oxidative metabolism. However, higher-intensity zones burn more total calories per session, which matters more than the fat-burning percentage. Both approaches work; the best zone is the one you'll sustain consistently.
Can I use this with a heart rate monitor?
Yes — set zone alarms on your device using the bpm ranges from this calculator. Most modern GPS watches allow custom zone setup. These zones are more accurate than device defaults, which typically use only age (220−age) without your resting HR.