Target Heart Rate Calculator

Understanding Heart Rate

Heart rate measures how many times your heart beats per minute (bpm). This calculator helps you determine your optimal exercise intensity by calculating your target heart rate zones based on key cardiovascular metrics.

Key Concepts

Maximum Heart Rate (MHR)

The highest heart rate achievable during intense exercise. While best measured through clinical stress tests, we estimate it using formulas:

1. Haskell & Fox (1971): 220 - age
2. Tanaka, Monahan & Seals (2001): 208 - (0.7 × age)
3. Nes et al. (2013):
   • Men: 211 - (0.64 × age)
   • Women: 211 - (0.64 × age) - (0.2 × age)

Note: These are population averages – individual maximum heart rates can vary significantly.

Resting Heart Rate (RHR)

Your heart rate at complete rest (measured best in the morning before rising). Healthy ranges:

• Average adult: 50-90 bpm
• Athletes often have 40-60 bpm

Heart Rate Reserve (HRR)

The difference between your maximum and resting heart rates:
HRR = MHR - RHR

Target Heart Rate Zones

Five intensity zones provide different training benefits:

Zone	Intensity	% of HRR	Benefits
1	Very Light	50-60%	Warm-up, recovery
2	Light	60-70%	Fat burning, endurance
3	Moderate	70-80%	Aerobic fitness
4	Hard	80-90%	Anaerobic threshold
5	Maximum	90-100%	Peak performance

Calculation Methods

1. Haskell & Fox Method

Simplest method using only age:
Target HR = MHR × intensity%

2. Karvonen Formula (Recommended)

More accurate, using HRR:
Target HR = (HRR × intensity%) + RHR

3. Perceived Exertion Scales

Alternative subjective methods:

Borg Scale (6-20):
THR = RHR + (MHR-RHR) × (RPE-6)/14

Modified Borg CR10 (0-10):
THR = RHR + (MHR-RHR) × (RPE/10)

How to Use This Calculator

1. Enter your age and gender
2. Input resting heart rate (if known)
3. Select calculation method
4. View your personalized target zones
5. Use these ranges to optimize your workouts

For best results, combine heart rate monitoring with perceived exertion for a complete picture of your workout intensity.