Heart Rate Zone Calculator
Training hard every day is not training smart — the most effective sessions are built around heart rate zones, from easy fat-burn efforts to all-out sprints. This free calculator estimates your maximum heart rate from your age and breaks it into five training zones, each with target beats per minute so you know exactly what your watch should show.
Heart Rate Zone Calculator
How to Use This Calculator
Enter your age and choose the formula used to estimate your maximum heart rate. The Tanaka formula (208 − 0.7 × age) is the default because it fits real-world data slightly better than the traditional 220 minus age, especially for adults over 40 — but switch to the traditional formula to compare the two.
Click Calculate and the tool shows your estimated max heart rate in beats per minute, plus the five training zones as target heart rate ranges. Each zone spans 10% of your max: Zone 1 and 2 are the easy aerobic work that builds your base, Zone 3 is steady cardio, and Zone 4 and 5 are the hard efforts that push your limit.
Use the ranges with any heart rate monitor or fitness watch. Aim your easy days at Zone 2, your long steady runs at Zone 3, and your tempo runs or intervals at Zones 4–5 — a typical week has far more time in the low zones than the high ones.
The Formula
Your max heart rate is estimated from age: Tanaka: max HR = 208 − 0.7 × age, or traditional: max HR = 220 − age. Each zone is a percentage band of that maximum: Zone 1 is 50–60%, Zone 2 is 60–70%, Zone 3 is 70–80%, Zone 4 is 80–90% and Zone 5 is 90–100%, with the boundary beats per minute rounded to whole numbers.
Worked example: a 30-year-old using the Tanaka method has a max heart rate of 208 − 0.7 × 30 = 208 − 21 = 187 bpm. Zone 2, the fat-burn endurance zone, runs from 60% to 70% of max: 0.60 × 187 ≈ 112 bpm up to 0.70 × 187 ≈ 131 bpm. So the watch target for an easy base run is 112–131 bpm.
Tips
Use the talk test to sanity-check the zones. In Zone 2 you should be able to hold a comfortable conversation; in Zone 3 you can only manage short sentences; in Zone 4 and 5 talking is difficult or impossible. If your perceived effort and the numbers disagree, trust how you feel.
Do most of your training in Zone 2. The easy aerobic miles build the engine — bigger blood vessels, stronger heart muscle, better fat use — and they let you recover between hard days. A typical week for a recreational runner is 70–80% easy work and 20–30% hard.
Your numbers change as you get fitter and as you age. Recalculate your zones every few months, and if you use a chest strap or watch with a measured max, plug your real number into the zones yourself — the percentages are the same, only the max changes.
Frequently Asked Questions
How do I find my maximum heart rate?
The easiest safe method is the one in this calculator: estimate it from your age. The most accurate way is a graded exercise test done in a lab or with a sports doctor. You can also get a rough number from a hard all-out effort, like a 10K race, while wearing a heart rate monitor.
Which heart rate zone burns the most fat?
Zone 2 (60–70% of max) burns the highest percentage of calories from fat, which is why it is called the fat-burn zone. But total fat burned depends on total calories, so a harder session in Zone 3 or 4 can still burn more fat overall.
How long should I train in zone 2?
Most runners and cyclists build their base with 30–90 minutes in Zone 2, three to five times a week. It feels easy, which is the point: you can do more of it, recover faster, and it builds the aerobic engine everything else sits on.
Is the 220-minus-age formula accurate?
It is a rough population average and can be off by 10–15 bpm for any individual. The Tanaka formula used here (208 − 0.7 × age) is slightly more accurate for most people, but only a measured test tells you your real number.
What is a good resting heart rate?
For adults, a normal resting heart rate is 60–100 bpm, and well-trained athletes often sit at 40–60 bpm. Measure it in the morning before you get out of bed, take the average over a few days, and talk to a doctor if it is consistently above 100 or below 40.