Is fat-burn zone best for weight loss?
Total weekly calorie deficit matters more than staying in one zone.
Fat-Burning Heart Rate Calculator
Get the classic 60–70% heart-rate band often labeled the fat-burn zone.
Age and optional resting HR
Max HR ≈ 220 − age. Resting HR enables Karvonen personalization.
About this calculator
How to use Fat-Burning Heart Rate Calculator, plus the formulas and logic behind the results.
Tool description
The fat-burn zone is moderate cardio where a higher share of energy can come from fat—but total calorie burn matters more for weight loss over time.
How to use
- Enter age.
- Add resting HR if you know it.
- Calculate the bpm range.
- Stay in range with talk-test easy-moderate effort.
Formulas & reference
Zone = 60–70% of max HRKarvonen: (max − rest) × % + restMax HR ≈ 220 − age
Using the zone
- Easy walks and light cardio
- Long duration 30–60+ min
- Should feel sustainable
- Pair with diet for fat loss
Calculation logic
Computes lower and upper bpm at 60% and 70% using Karvonen when resting HR supplied, else plain % of max.
You still burn calories above this zone; higher intensities burn more total energy per minute.
Fat-Burning Heart Rate Calculator FAQ
Common questions about this calculator and how to use the results.
Do I burn zero fat above 70%?
No—you burn mixed fuels at all intensities.
Chest strap vs watch?
Straps track intervals better; watches are fine for steady cardio.
Medications affect HR?
Beta blockers lower HR—ask your doctor before training by zones.
Fasted cardio in this zone?
Personal preference; total daily intake drives fat loss.
How long in the zone?
30–45 minutes most days is a common starting point for beginners.