Health & Fitness
Heart Rate Zone Calculator
Use this heart-rate zone calculator to estimate easy, aerobic, tempo, threshold, and high-intensity training ranges.
Zone 2 range
—
- Estimated max HR
- —
- Zone 5 starts
- —
Student quick launch
Grade planning, algebra checks, and formulas students reach for most.
Study path
Use this calculator with
Follow these when you want the formula behind the answer, a short lesson, or nearby tools in the same topic.
What the heart rate zone calculator solves
Use this heart-rate zone calculator to estimate easy, aerobic, tempo, threshold, and high-intensity training ranges.
Formula
How to use it
- Enter age.
- Enter resting heart rate for Karvonen zones.
- Choose the method and read zone ranges.
How to read the answer
Zone 2 is commonly used for easy aerobic work; higher zones are progressively harder.
Common mistakes and edge cases
- Estimated max HR can be off by a lot.
- Wrist sensors can lag or misread.
- Medical conditions and medications can alter heart rate.
Worked examples
Karvonen zones
Zone 2 range
135-148 bpm
Percent max zones
Zone 2 range
105-122 bpm
Frequently asked questions
Which method is better?+
Karvonen accounts for resting heart rate, but both are estimates.
What is Zone 2?+
A moderate aerobic range often used for endurance base training.
Related calculators
Pace Calculator
Calculate running pace, speed, finish time, and split time from distance and duration.
VO2 Max Calculator
Estimate VO2 max from Cooper 12-minute distance with pace and fitness interpretation.
Calorie Calculator
Estimate daily maintenance calories from age, sex, height, weight, and activity using BMR and TDEE.
BMI Calculator
Calculate adult BMI from metric or imperial measurements, see CDC-style categories, healthy weight range, and target BMI weight.
BMR Calculator
Estimate basal metabolic rate using the Mifflin-St Jeor equation with clear formula substitution.
Body Fat Calculator
Estimate body fat percentage using the U.S. Navy circumference method with measurement validation.
Last updated: May 8, 2026