What is target heart rate?
Target heart rate for exercise is the heart rate at which physical effort is the most effective. If it's too low, then the exercise won't bring the expected results, such as making you fitter. If it's too high, it may be dangerous for you. Your target heart rate should be between 50–85% of your maximum heart rate — that's your desired target heart rate zone.
But what exactly is heart rate? To put it simply, your heart rate is the number of times your heart beats per minute.
How to use the target heart rate calculator?
- Choose your unit system — metric (kg) or imperial (lbs).
- Enter your age — the calculator uses it to estimate your maximum heart rate.
- Set your exercise intensity — use the quick buttons (Light 55%, Fat Burn 65%, Cardio 75%, Peak 90%) or type a custom percentage between 50–100%.
- Optionally, enter your resting heart rate — this unlocks the Karvonen formula, which gives a more personalized target zone accounting for your fitness level.
- Optionally, enter your weight — this adds estimated calorie burn per hour to each zone.
- Click Calculate to see your results instantly.
How to calculate the target heart rate?
Method 1: Percentage of Maximum Heart Rate (Fox Formula)
The simplest and most widely used method:
Maximum HR = 220 − age Target HR = Maximum HR × intensity %
Example for a 35-year-old at 70% intensity:
- Maximum HR = 220 − 35 = 185 bpm
- Target HR = 185 × 0.70 = 130 bpm
Method 2: Karvonen Formula (Heart Rate Reserve)
A more precise approach that accounts for your resting heart rate (a proxy for fitness level):
HRR = Maximum HR − Resting HR Target HR = (HRR × intensity%) + Resting HR
Example for a 35-year-old, resting HR 60 bpm, at 70% intensity:
- Maximum HR = 220 − 35 = 185 bpm
- HRR = 185 − 60 = 125 bpm
- Target HR = (125 × 0.70) + 60 = 87.5 + 60 = 148 bpm
The Karvonen method is recommended for athletes and regularly active individuals since it reflects personal fitness.
Average target heart rate chart
| Age | Max HR (bpm) | Target Zone 50–85% (bpm) |
|---|---|---|
| 20 | 200 | 100–170 |
| 25 | 195 | 98–166 |
| 30 | 190 | 95–162 |
| 35 | 185 | 93–157 |
| 40 | 180 | 90–153 |
| 45 | 175 | 88–149 |
| 50 | 170 | 85–145 |
| 55 | 165 | 83–140 |
| 60 | 160 | 80–136 |
| 65 | 155 | 78–132 |
| 70 | 150 | 75–128 |
Target heart rate zones explained
- Zone 1 — Light (50–60% MHR): Warm-up and recovery. Easy walking, gentle cycling. Burns mostly fat at low intensity.
- Zone 2 — Fat Burn (60–70% MHR): Moderate effort. The classic "fat-burning zone." Comfortable pace — you can hold a full conversation. Ideal for weight loss and endurance base building.
- Zone 3 — Cardio / Aerobic (70–85% MHR): Harder effort. Improves cardiovascular fitness and aerobic capacity. Typical for steady-state runs, cycling, or swimming. You can speak only in short sentences.
- Zone 4 — Peak / Anaerobic (85–95% MHR): High-intensity training. Builds speed and power. Suitable for HIIT intervals. Difficult to sustain for long.
Tips for monitoring your heart rate during exercise
- Use a chest strap heart rate monitor for the most accurate readings during exercise.
- Wrist-based optical sensors (smartwatches) are convenient but slightly less accurate during intense movement.
- You can check manually: place two fingers on your wrist (radial pulse) or neck (carotid pulse) and count beats for 15 seconds, then multiply by 4.
- Beginners should start in Zone 1–2 and gradually progress.
- Always warm up before reaching your target zone and cool down afterward.
- If you feel dizzy, short of breath, or experience chest pain — stop and rest immediately.