What are heart rate zones?
Heart rate zones are ranges of beats per minute (bpm) that match different exercise intensities. Training in the right zone helps you reach your goal — whether that is burning fat, improving stamina, lowering blood pressure or getting faster. Your zones are based on your maximum heart rate, which falls gradually with age, and — for more accuracy — your resting heart rate.
How the heart rate zone calculator works
1. Maximum heart rate
- Tanaka formula (recommended): max HR = 208 − 0.7 × age
- Classic formula: max HR = 220 − age
2. Karvonen formula (if you enter resting heart rate)
Target HR = (max HR − resting HR) × intensity % + resting HR. This uses your heart rate reserve, so a fitter person with a low resting heart rate gets more personal zones. Without resting heart rate, zones are a simple percentage of max HR.
Example: a 40-year-old with a resting heart rate of 60 bpm: classic max HR = 180 bpm. Zone 3 (70–80%) = (180 − 60) × 0.7 + 60 = 144 to (180 − 60) × 0.8 + 60 = 156 bpm.
The five heart rate training zones
| Zone | Intensity | How it feels | Main benefit |
|---|---|---|---|
| Zone 1 – Very light | 50–60% | Easy, can chat freely | Warm-up, recovery, beginners |
| Zone 2 – Light (“fat-burning”) | 60–70% | Comfortable, can hold a conversation | Endurance base; highest share of energy from fat |
| Zone 3 – Moderate | 70–80% | Breathing harder, short sentences | Aerobic fitness and heart health |
| Zone 4 – Hard | 80–90% | Few words at a time | Speed, lactate threshold |
| Zone 5 – Maximum | 90–100% | All-out, can’t talk | Short sprints; for fit, healthy people only |
Resting heart rate: low, normal and high
| Resting heart rate (adults) | Level |
|---|---|
| Below 60 bpm | Low — normal in fit people; see a doctor if you feel dizzy or faint |
| 60 – 100 bpm | Normal (60–80 bpm is ideal for most) |
| Above 100 bpm | High (tachycardia) — speak to your doctor |
Benefits of training by heart rate
- Burn more fat comfortably: zone 2 sessions are easy to sustain for 30–60 minutes and build endurance.
- Avoid overtraining and injuries by keeping easy days truly easy.
- Improve heart health: regular zone 2–3 exercise lowers resting heart rate and blood pressure.
- Track fitness progress: as you get fitter, the same pace feels easier and your heart rate drops.
Health warnings
- Formulas estimate max heart rate within about ±10 bpm. An exercise stress test is the only accurate way to measure it.
- Beta-blockers and some heart medicines lower your heart rate — follow your doctor’s advice and use perceived effort instead.
- If you have heart disease, high blood pressure, diabetes or are pregnant, get medical clearance before high-intensity training (zones 4–5).
- Stop exercising immediately and seek help if you have chest pain, an irregular heartbeat, severe breathlessness or dizziness.
- In hot weather your heart rate rises faster — slow down and drink water.
Putting your zones to work
A balanced week might include three or four 30–45 minute zone 2 sessions (brisk walking, cycling, swimming), one zone 3–4 session, and two strength workouts. Estimate your energy use with the calories burned calculator, fuel your training with our sports nutrition guide, and support heart health with the DASH diet.
Frequently asked questions
What is my fat-burning heart rate?
The “fat-burning” zone is usually zone 2, about 60–70% of your maximum heart rate. For a 40-year-old, that is roughly 108–126 bpm using the 220 − age formula.
How do I calculate my maximum heart rate?
The simplest estimate is 220 minus your age. The Tanaka formula, 208 − 0.7 × age, is more accurate for many adults, especially those over 40.
What is the Karvonen formula?
The Karvonen formula uses your heart rate reserve (max HR minus resting HR): target HR = (max − resting) × intensity + resting. It gives more personal zones than a simple percentage of max HR.
What is a good resting heart rate?
For most adults 60–80 bpm is good, and anything from 60 to 100 bpm is considered normal. Fit people and athletes often have resting heart rates in the 40s or 50s.
Do I need to train in zone 5?
No. Most health and weight-loss benefits come from zones 2 and 3. Zone 5 is for short intervals in healthy, well-trained people.
Sources
- Tanaka H, Monahan KD, Seals DR. Age-predicted maximal heart rate revisited. J Am Coll Cardiol 2001;37:153–156.
- Karvonen MJ, et al. The effects of training on heart rate. Ann Med Exp Biol Fenn 1957;35:307–315.
- American Heart Association. Target heart rates chart.
- WHO guidelines on physical activity and sedentary behaviour. 2020.