The Calorie Burn Calculator estimates how many calories you burn during specific physical activities based on your body weight, the activity type, and the duration — using metabolic equivalent (MET) values from exercise science research.

How to Use This Calculator

1. Enter your body weight.
2. Select the activity from the list.
3. Enter the duration in minutes.
4. Click Calculate.

Calorie Burn by Activity (per 30 min, 155 lb person)

• Running (6 mph): ~372 calories
• Cycling (moderate): ~260 calories
• Swimming (vigorous): ~300 calories
• Walking (3.5 mph): ~149 calories
• Weight training: ~112 calories
• Yoga: ~149 calories
• HIIT: ~298–372 calories

Why Heavier People Burn More Calories

The calorie burn formula multiplies MET × body weight in kg × time in hours. This means a heavier person burns more calories doing the same activity for the same duration — because more energy is required to move more mass. This is why calorie counts on gym equipment that don’t ask for weight are often inaccurate.

Over time, as you lose weight, the same workout burns fewer calories — one reason weight loss often slows even with consistent exercise. Adjusting workout intensity or duration compensates for this effect.

Limitations of Calorie Estimates

MET-based calculations are averages. Individual calorie burn varies by 10–20% based on fitness level, metabolism, genetics, and exercise technique. Wearable fitness trackers improve accuracy by incorporating heart rate data, but still overestimate calorie burn by an average of 27% (Stanford study, 2017).

Use this calculator to estimate trends and compare activities — not as a precise accounting tool for eating back exercise calories.

Frequently Asked Questions

What is a MET value?

MET stands for Metabolic Equivalent of Task. A MET of 1 is the energy expended sitting at rest. Walking at 3.5 mph has a MET of about 3.5 (3.5× resting energy). Running at 6 mph has a MET of about 10. The Compendium of Physical Activities (Ainsworth et al.) maintains the most comprehensive database of MET values.

Does exercise after-burn count?

Yes — EPOC (Excess Post-Exercise Oxygen Consumption) means your body burns extra calories for hours after intense exercise. HIIT and heavy strength training produce the most EPOC. This calculator only estimates calories burned during the activity itself, not post-exercise burn.