How accurate is a calories burned calculator?

MET-based calculators provide a reasonable estimate — typically within 15-20% of actual calorie burn for most people. They are most accurate for steady-state activities like walking, running, and cycling. Factors like fitness level, body composition, and exercise technique can cause individual variation. For precise measurement, a heart rate monitor or metabolic testing is needed.

What are MET values and how are they determined?

MET (Metabolic Equivalent of Task) is a standardized measure of exercise intensity developed through laboratory research. A MET of 1.0 equals the energy cost of sitting quietly (~1 kcal/kg/hour). MET values are cataloged in the Compendium of Physical Activities, maintained by researchers at Arizona State University, based on oxygen consumption measurements during various activities.

Does body weight really affect how many calories I burn?

Yes, significantly. A heavier person requires more energy to move their body through any activity. For example, a 90 kg person running for 30 minutes burns about 50% more calories than a 60 kg person running at the same pace. This is why the formula multiplies MET by body weight — it accounts for the energy cost of moving your specific mass.

Which activity burns the most calories?

Among common activities, boxing (12.8 MET), HIIT (12.0 MET), and jump rope (11.0 MET) have the highest MET values. However, the "best" activity is one you can sustain consistently. A moderate activity done regularly burns far more total calories over time than an intense activity you do once and quit. Choose something you enjoy.

How many calories should I burn per day to lose weight?

Weight loss requires a calorie deficit — burning more than you consume. A deficit of 500 calories per day leads to roughly 0.5 kg (1 lb) of weight loss per week. However, exercise alone is rarely enough — most people achieve better results by combining increased activity with moderate dietary changes. Use our TDEE calculator for a complete picture of your daily energy needs.

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Calories Burned Calculator

Estimate how many calories you burn during any activity based on your weight and duration.

How Calories Burned Is Calculated

This calculator uses MET (Metabolic Equivalent of Task) values — a standardized measure of exercise intensity:

Calories = MET × Weight (kg) × Duration (hours)

Enter your weight

Your body weight directly affects how many calories you burn. A heavier person burns more calories performing the same activity because their body requires more energy to move.

Choose your activity

Each activity has a MET value that represents its energy cost relative to rest. For example, running at 6 mph (MET 9.8) burns roughly 3 times more energy than walking at 3.5 mph (MET 4.3).

Get your estimate

The formula multiplies your MET value, weight in kilograms, and duration in hours to give you an estimated calorie burn. This is a solid approximation used by exercise physiologists worldwide.

How MET Values Work — And Why Weight Matters

MET (Metabolic Equivalent of Task) is a unit that expresses the energy cost of physical activity. A MET of 1.0 represents the energy you burn at rest — sitting quietly. Every activity has a MET value relative to this baseline. The higher the MET, the more intense the activity.

1 MET equals approximately 1 kcal per kilogram of body weight per hour — this is your resting metabolic rate while sitting quietly
MET values scale linearly with body weight — a 90 kg person burns 50% more calories than a 60 kg person doing the same activity at the same MET level
MET values range from 1.0 (rest) to over 20 (sprinting) — most moderate exercises fall between 3.0 and 8.0 MET
MET values represent averages from research studies — your actual calorie burn depends on your fitness level, technique, and exercise intensity
Heavier individuals burn more calories because it takes more energy to move a larger body — this is physics, not an assumption
High-intensity activities (MET > 8) trigger excess post-exercise oxygen consumption (EPOC), meaning you continue burning extra calories for hours after the workout

Tips to Maximize Your Calorie Burn

1Increase intensity gradually — switching from walking (4.3 MET) to jogging (7.0 MET) nearly doubles your calorie burn per minute
2Add bodyweight training — muscle tissue burns more calories at rest than fat, so building muscle increases your 24-hour energy expenditure
3Try HIIT workouts — high-intensity interval training (12.0 MET) burns significantly more calories in less time and triggers a strong afterburn effect
4Prioritize consistency over duration — four 30-minute sessions per week burn more total calories than one 2-hour session
5Boost your NEAT — non-exercise activity thermogenesis (walking, standing, fidgeting) accounts for 15-30% of daily calorie expenditure
6Focus on compound movements — exercises that engage multiple muscle groups (squats, push-ups, burpees) burn more calories than isolation exercises

Common Calorie Burning Myths Debunked

"Sweating more means you burn more calories"

Sweat is your body's cooling mechanism, not a calorie counter. You can sweat profusely in a hot room doing nothing while burning minimal calories. Conversely, swimming in cold water burns significant calories with minimal sweat. Calorie burn depends on exercise intensity (MET) and duration, not perspiration.

"You need to exercise for at least 30 minutes to burn fat"

Your body burns a mix of fuel sources from the very first second of exercise. While longer sessions do increase total fat oxidation, even 10-minute bouts of activity contribute to calorie burn and health benefits. What matters most is total energy expenditure over days and weeks, not hitting a magic duration threshold.

"Cardio burns more calories than strength training"

While cardio typically has a higher per-minute calorie burn during the session, strength training creates an afterburn effect (EPOC) that elevates your metabolism for 24-72 hours post-workout. Additionally, the muscle you build increases your resting metabolic rate permanently. A combination of both is optimal for maximizing total calorie expenditure.

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Frequently Asked Questions

How accurate is a calories burned calculator?: MET-based calculators provide a reasonable estimate — typically within 15-20% of actual calorie burn for most people. They are most accurate for steady-state activities like walking, running, and cycling. Factors like fitness level, body composition, and exercise technique can cause individual variation. For precise measurement, a heart rate monitor or metabolic testing is needed.
What are MET values and how are they determined?: MET (Metabolic Equivalent of Task) is a standardized measure of exercise intensity developed through laboratory research. A MET of 1.0 equals the energy cost of sitting quietly (~1 kcal/kg/hour). MET values are cataloged in the Compendium of Physical Activities, maintained by researchers at Arizona State University, based on oxygen consumption measurements during various activities.
Does body weight really affect how many calories I burn?: Yes, significantly. A heavier person requires more energy to move their body through any activity. For example, a 90 kg person running for 30 minutes burns about 50% more calories than a 60 kg person running at the same pace. This is why the formula multiplies MET by body weight — it accounts for the energy cost of moving your specific mass.
Which activity burns the most calories?: Among common activities, boxing (12.8 MET), HIIT (12.0 MET), and jump rope (11.0 MET) have the highest MET values. However, the "best" activity is one you can sustain consistently. A moderate activity done regularly burns far more total calories over time than an intense activity you do once and quit. Choose something you enjoy.
How many calories should I burn per day to lose weight?: Weight loss requires a calorie deficit — burning more than you consume. A deficit of 500 calories per day leads to roughly 0.5 kg (1 lb) of weight loss per week. However, exercise alone is rarely enough — most people achieve better results by combining increased activity with moderate dietary changes. Use our TDEE calculator for a complete picture of your daily energy needs.