Fitness & Performance
Target Heart Rate Calculator
Training in the right zone is the difference between burning fat, building endurance, or wasting a session. Get your five zones.
Target heart rate is the beats-per-minute range where exercise is most effective, usually 50–85% of your maximum heart rate, estimated as 220 minus age. The Karvonen formula refines this using resting heart rate. Use the result as a training benchmark — retest under the same conditions to track progress.
Max HR ≈ 220 − age.
Karvonen adds resting HR.
Zones: 50–60% warm-up to 90–100% max effort.
Calculate Your Target Heart Rate
Your Training Heart Rate
What Is Target Heart Rate?
Target heart rate zones translate effort into numbers. Most cardiovascular benefits come from training between 60% and 85% of max heart rate.
This calculator uses the Karvonen formula, which incorporates resting heart rate for more personalized zones than the simple percentage-of-max method.
How It Is Calculated
HRmax = 220 − age (est.)
Karvonen: target = resting HR + % × (HRmax − resting HR)
Example: Example: age 35, resting 62 → HRmax 185, aerobic zone ≈ 148–160 bpm
The five training zones
| Zone | % HRR | Feels like | Purpose |
|---|---|---|---|
| 1 · Warm-up | 50–60% | Very light | Recovery, warm-up |
| 2 · Fat burn | 60–70% | Conversational | Base endurance |
| 3 · Aerobic | 70–80% | Steady effort | Cardio fitness |
| 4 · Threshold | 80–90% | Hard, controlled | Lactate threshold |
| 5 · Max | 90–100% | All-out | Speed, VO2 max |
Limitations
- 220 − age is a population estimate; individual max HR varies ±12 bpm.
- Beta blockers and other medications lower heart rate, zones must be adjusted.
- Perceived exertion (talk test) is a valid fallback when zones feel wrong.
Sources & Review
References used for this calculator’s formulas and thresholds:
Target Heart Rate FAQ
What should my heart rate be when exercising?
60–80% of max for most training. For a 35-year-old (max ≈185), that's roughly 111–148 bpm without Karvonen adjustment.
What is the fat-burning zone?
Zone 2, about 60–70% of max, the highest proportion of fat as fuel. Total calories burned still matters more for weight loss.
Why use Karvonen instead of simple percentages?
Karvonen includes your resting heart rate, so a fit person with a low resting pulse gets accurate, personalized zones.
How do I measure resting heart rate?
Take your pulse first thing in the morning, before coffee, lying down, for 60 seconds, average three days.
Please read this first: these results are educational estimates. For real decisions, talk to a qualified professional.