Heart Rate Zone Calculator

How heart rate zones are calculated

Max HR ≈ 220 − age Target HR (Karvonen) = resting HR + (max HR − resting HR) × intensity

The heart rate reserve method accounts for your fitness through your resting heart rate. Without it, zones are a simple percentage of max.

Worked example

A 40-year-old has an estimated max of 220 − 40 = 180 bpm. With a resting rate of 60, the reserve is 120 bpm, so zone 2 (60–70%) is 60 + 120 × 0.6 to 60 + 120 × 0.7 = 132–144 bpm.

What each zone trains

Zone	Feels like	Main benefit
1	Very easy	Recovery
2	Easy, can talk	Aerobic base and endurance
3	Moderate	Aerobic fitness
4	Hard	Lactate threshold
5	All-out	Maximum effort, short bursts

Check with a doctor before starting a new exercise program, especially if you have heart conditions or take medication that affects heart rate.

Frequently asked questions

Is 220 minus age accurate?

It is a rough average. A lab or field test gives a more accurate personal maximum.

What is a good resting heart rate?

For adults, 60–100 bpm is the typical range; fit people are often lower.

Which zone burns the most fat?

Lower zones use a higher share of fat, but higher zones burn more total energy per minute.

Do beta blockers affect heart rate zones?

Yes. Some medications lower heart rate, so age-based zones may not apply. Ask your doctor.