For what does the Karvonen formula calculate?

The Karvonen formula calculates your personalized target heart rate (THR) for different exercise intensities. It uses your maximum heart rate and resting heart rate to create training zones that are tailored to your individual fitness level.

How do I find my Maximum Heart Rate (MHR)?

The simplest and most common method is to use the formula: 220 − your age. For example, if you are 40 years old, your estimated MHR would be 180 bpm.

How to find target heart rate?

You can find your target heart rate using the full Karvonen Formula: THR = ((Maximum Heart Rate − Resting Heart Rate) × %Intensity) + Resting Heart Rate.

What is the best target heart rate zone for fat burning?

The optimal fat-burning zone is Zone 2, which corresponds to a light intensity of about 60–70% of your heart rate reserve. Training in this zone encourages your body to use fat as its primary fuel source.

Is the Karvonen method accurate?

Yes, it is one of the most accurate methods for determining workout intensity because it factors in your personal resting heart rate. It is highly recommended by the American College of Sports Medicine (ACSM).

Karvonen Formula Calculator: Find Your Ideal Heart Rate

What is the Karvonen Formula?

The Karvonen formula is a scientific method of calculating your target heart rate zones based on a person's heart rate reserve, which is the difference between maximum heart rate and resting heart rate. This method factors in your fitness level, which gives you much more accurate heart rate zones than general “220 - age” formulas.

The Formula

Target Heart Rate (THR) = ((MHR − RHR) × Intensity) + RHR

MHR: Maximum Heart Rate (220 − age)

RHR: Resting Heart Rate

Intensity: e.g., 70% = 0.7

What is used in calculating the Karvonen Formula?

The Karvonen formula is used for:

Estimate your exercise intensity for goals, such as fat burning or improving stamina.
Find your heart rate reserve—the most accurate indicator of cardiovascular fitness.
Tailor your workouts rather than relying on general age-based charts.

It is widely used by athletes, fitness trainers, and physiologists because it reflects your real fitness level and not just your age.

Why Use Our Karvonen Formula Calculator?

Our HR Training Calculator makes heart rate training easy, accurate, and insightful. It:

Instant Calculations

Instantly calculates target heart rate zones for any intensity level.

For Everyone

Works for beginners and athletes alike, with personalized results.

Detailed Zones

Displays fat-burning, endurance, and peak performance zones.

Track Progress

Helps you track progress and recovery over time.

How to Calculate Karvonen Formula (Step-by-Step)

Step 01

Measure Your Resting Heart Rate (RHR)

Take your pulse for 30 seconds and multiply by 2. Average this over 3 mornings for accuracy.

Step 02

Calculate Your Maximum Heart Rate (MHR)

Use the simple formula: 220 − your age. For a 30-year-old, the MHR is 190 bpm.

Step 03

Choose Your Workout Intensity

Decide your target training zone, for example, 70% for moderate aerobic exercise.

Step 04

Apply the Karvonen Formula

Input your values into the formula: ((MHR − RHR) × Intensity) + RHR to get your target heart rate.

Example Calculation

Age: 30, RHR: 70 bpm, Intensity: 70%

1. MHR: 220 - 30 = 190 bpm

2. HRR: 190 (MHR) - 70 (RHR) = 120

3. Apply Intensity: 120 × 0.7 = 84

4. Final THR: 84 + 70 (RHR) = 154 bpm

Understanding Your Heart Rate Zones

Each heart rate zone corresponds to a specific intensity and provides a different physiological benefit. Training across different zones creates a well-rounded fitness regimen.

Zone 1: Recovery

50-60%

Prepares body for exercise, aids in recovery.

Zone 2: Endurance

60-70%

Builds aerobic base and burns fat efficiently.

Zone 3: Aerobic

70-80%

Improves cardiovascular fitness and stamina.

Zone 4: Threshold

80-90%

Increases lactate threshold and speed.

Zone 5: Max Effort

90-100%

Develops peak power and anaerobic capacity.

Karvonen Formula Heart Rate Zones Calculation

Here is an example table for a 30-year-old individual with a resting heart rate of 70 bpm.

Zone	Intensity	Heart Rate Range	Training Goal
Zone 1	50–60%	130–142 bpm	Warm-up, recovery
Zone 2	60–70%	142–154 bpm	Fat burning, endurance
Zone 3	70–80%	154–166 bpm	Aerobic training
Zone 4	80–90%	166–178 bpm	Performance, VO₂max
Zone 5	90–100%	178–190 bpm	Sprinting, peak effort

Who Should Use This Calculator?

Fitness enthusiasts tracking their workout intensity
Runners, cyclists, and swimmers training for endurance
People targeting fat loss through zone 2 training
Anyone wanting to improve cardiovascular efficiency

Benefits of Using the Karvonen Formula Calculator

Prevents Overtraining

Keeps the intensity of exercises within safe zones. This formula, developed by Martti Karvonen in 1957, makes use of Heart Rate Reserve, a mainstay in sports science, to equate heart rate zones with VO₂max percentages, or oxygen consumption. That's why it is more reliable than basic methods of determining the cardiovascular load.

Global Guidelines

The principles of heart rate training are recognized worldwide:

United States: Follows the AHA exercise intensity guidelines.
United Kingdom: Aligns with NHS heart health recommendations.
India: Ideal for both home and gym use by users of all fitness levels.
UAE: Perfect for hot climate endurance and sports trainings, subtract 5–10 bpm.

Scientific References and Further Reading

Original Karvonen Study
Karvonen, M. J., Kentala, E., & Mustala, O. (1957). The effects of training on heart rate; a longitudinal study. Annales Medicinae Experimentalis et Biologiae Fenniae.
→ View on PubMed
ACSM Guidelines for Exercise Prescription
American College of Sports Medicine. (2018). ACSM's guidelines for exercise testing and prescription (10th ed.). Wolters Kluwer.
→ View on ACSM
Maximal Heart Rate Formula Comparison
Tanaka, H., Monahan, K. D., & Seals, D. R. (2001). Age-predicted maximal heart rate revisited. Journal of the American College of Cardiology.
→ View on PubMed

Karvonen Formula Calculator