Heart Rate Zone Calculator
Instant results as you type.
For education only — this is not medical advice. The figures are population averages: real energy use, appetite and rate of loss vary from person to person, and weight loss slows as you get lighter. If you are pregnant, managing diabetes, heart or joint conditions, or taking medication, talk to a doctor before changing your diet or activity.
Training zones turn a heart rate monitor into something useful — they tell you whether an easy run is genuinely easy and whether a hard effort is hard enough. This calculator estimates your maximum heart rate using the Tanaka formula, which is more accurate than the familiar 220 minus age, and derives five zones. Give it your resting heart rate and it uses the Karvonen method instead, which is more personal.
How to use it
- Enter your age.
- Optionally add your resting heart rate, measured on waking before getting up.
- Read the five zones, and which method was used.
Examples
- At 30, the estimated maximum is 187 bpm and zone 2 runs 112 to 131.
- Adding a resting rate of 60 switches to Karvonen and shifts the zones upward.
Frequently asked questions
- What is my maximum heart rate?
- This calculator estimates it as 208 minus 0.7 times your age — 187 bpm at age 30. It is an estimate from population data, and individual maximums vary by 10 to 12 beats either side. The only accurate way to know yours is a supervised maximal test, which is not something to attempt casually.
- Why not use 220 minus age?
- Because it was never derived from careful research — it came from a rough fit to limited data and has been widely criticised since. It systematically underestimates maximum heart rate in older adults, which pushes their training zones too low. The Tanaka equation used here fits the evidence better across ages.
- What is zone 2 training and why is it popular?
- Zone 2 is a conversational effort, around 60 to 70 per cent of maximum, where the body relies heavily on fat for fuel and builds aerobic capacity with little fatigue cost. Its popularity comes from the finding that most endurance athletes spend the majority of their training there — the common amateur mistake is running the easy days too hard.
- Does a resting heart rate make the zones more accurate?
- Yes, meaningfully. The Karvonen method works from heart-rate reserve — the gap between resting and maximum — so it adapts to your fitness rather than assuming an average. As training lowers your resting rate, the zones shift with it. Measure it on waking, before coffee and before getting out of bed.