Target Heart Rate Zones
Training zones from age, optional resting pulse, Fox or Tanaka max HR, and Karvonen when rest is entered
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Leave resting at 0 to use percent of max HR. A morning pulse after sitting quietly is the usual rest value.
Max HR formula
Estimates only. Not medical advice and not a diagnosis. Talk to a clinician about your own numbers. Stop if you feel chest pain, dizziness or unusual shortness of breath.
About this tool
Training zones are percentages of max heart rate, or of heart-rate reserve when you enter a resting pulse (Karvonen). Max HR here is either Fox (220 minus age) or Tanaka (208 minus 0.7 times age). Both are population estimates; a lab test or a recent hard effort is better. Chest pain, dizziness or unusual breathlessness is a reason to stop and get care. Estimates only. Not medical advice.
How to use this tool
- Enter ageMax HR formulas are age-based. Tanaka is the default.
- Optional: resting pulseA morning seated pulse makes Karvonen zones. Set it to 0 to use percent of max only.
- Read zones 1 to 5Zone 2 is the easy aerobic / fat-burn band people usually mean.
How to calculate your target heart rate
Start with your maximum heart rate. The Fox formula is 220 minus your age; the Tanaka formula is 208 minus 0.7 x your age. For a 40-year-old both give 180 beats per minute. A training zone is a percentage of that maximum - for example 60 to 70% for easy, fat-burning work is 108 to 126 bpm.
The Karvonen method is more personal because it uses your resting pulse. Subtract resting heart rate from maximum to get your heart-rate reserve, take the percentage of that, and add the resting rate back. With a resting pulse of 60, the reserve is 120, so 70% is 60 + 84 = 144 bpm.
Key features
- Fox and Tanaka max HR side by side as a choice.
- Karvonen when rest HR is entered, percent of max when it is not.
- Zones labelled recovery, fat burn, tempo, threshold and VO2 max.
- Private in your browser.
Common uses
- Setting a watch's fat-burn or zone 2 alert.
- A walk/run plan that wants an easy aerobic cap.
- Comparing 220-minus-age with Tanaka before a coaching session.
Tips for better results
- Measure rest HR seated, after waking, before coffee.
- Zone 2 should feel like you can talk in sentences.
- Beta blockers and some other medicines change heart-rate training. Ask the prescriber.
Mistakes to avoid
- Living in zone 4 every session because the watch looks exciting.
- Using a standing or post-coffee pulse as rest HR.
- Ignoring symptoms because the number is "in zone 2".
Frequently asked questions
Zone = rest + percent of (max minus rest). It personalises the band if your resting pulse is low from fitness or high from stress.
It is a rough average. Tanaka is slightly better for many adults. A lab test or a recent hard effort is better still.
This page uses 60 to 70 percent of max (or of heart-rate reserve on Karvonen) as zone 2. Fat is still used at other intensities. The zone is about sustainable aerobic work.
Many endurance plans put most weekly time in the easy zones (roughly zones 1-2), where you can still talk in full sentences, with a smaller share of hard work in zones 4-5. Training hard every session tends to stall progress.
Take it in the morning before getting up, after lying still for a minute: count beats for 30 seconds and double it, or read it from a watch. Average several mornings for a reliable number.
Wrist sensors read blood flow optically and can lag or jump during intervals and strength work; chest straps read the heart's electrical signal and are usually more accurate for training zones.