Heart Rate Zone Calculator

Calculate your target heart rate training zones using the Karvonen (heart rate reserve) method, which factors in your resting heart rate for a more personalized result than max-HR-only formulas.

How the zones are calculated

• Maximum heart rate is estimated as 220 − your age, the common rule of thumb used by the American Heart Association.
• Heart rate reserve = maximum heart rate − resting heart rate.
• Target heart rate = (heart rate reserve × zone %) + resting heart rate.

Example zones

Zone	Age 30, resting 60 bpm	Age 45, resting 70 bpm	Age 60, resting 65 bpm
1 — Warm up (50–60%)	125–138	122–133	112–122
2 — Fat burn (60–70%)	138–151	133–144	122–132
3 — Aerobic (70–80%)	151–164	144–154	132–141
4 — Anaerobic (80–90%)	164–177	154–164	141–150
5 — Max effort (90–100%)	177–190	164–175	150–160

Using your zones

Most endurance plans spend the majority of training time in zones 1–2, which feel easy enough to hold a conversation, and use zones 4–5 for short, hard intervals. The "fat burn" name means a larger share of the energy comes from fat at that effort; you still burn more total calories per minute at higher zones.

The 220 − age estimate can be off by 10 beats per minute or more for some people. If your watch or a supervised exercise test shows a different maximum, the zones will be more accurate with your real number. Some medications, such as beta blockers, lower heart rate, so check with your doctor before using heart rate targets if you take them or have a heart condition.

Frequently asked questions

What is the Karvonen method?

It calculates target heart rate using heart rate reserve (max minus resting heart rate) rather than just a percentage of max — this accounts for individual fitness level, since two people with the same max heart rate can have very different resting rates.

How do I find my resting heart rate?

Check your pulse first thing in the morning, before getting out of bed, for a full 60 seconds — that gives the most accurate resting reading.

What does each zone mean?

Lower zones (50-70%) build a base and burn a higher percentage of fat as fuel; higher zones (70-90%) build cardiovascular fitness and speed but are more taxing to sustain.

What is a normal resting heart rate?

For most adults it's between 60 and 100 beats per minute, according to the American Heart Association. Well-trained athletes often have resting rates in the 40s or 50s.

What heart rate should I aim for during moderate exercise?

The American Heart Association puts moderate exercise at about 50–70% of your maximum heart rate and vigorous exercise at about 70–85%. This calculator uses heart rate reserve instead, which gives slightly higher numbers, but zones 1–2 broadly match moderate effort and zones 3–4 vigorous effort.