Why is the net figure lower?

Because you burn calories at rest anyway. Counting the gross figure against a diet deficit double-counts your resting metabolism for the duration of the workout.

Why does my watch disagree?

Wearables estimate from heart rate and their own models. Neither figure is measured; both are estimates from different assumptions.

Health & Fitnessfitness

Calories Burned Calculator

Calories burned from activity, using MET values. The gross figure includes what you would have burned sitting still, so the net figure is the honest one for anyone counting a deficit.

Also called: exercise calorie calculator, workout calories.

Calories burned

470.6

About 470.6 kcal in 45 minutes of running at 8 km/h, at 8.3 METs for a 72 kg body. Net of what you would have burned resting, that is 413.9 kcal. Over a week at 4 sessions it comes to 1,882.4 kcal. MET values are population averages, so an individual can differ by twenty percent or more.

Net of resting metabolism

413.9

MET value

8.3

Per minute

10.46

Weekly total

1,882.4

Equivalent in body fat

53.8

Activity

running at 8 km/h

On accuracy

MET values are population averages, so an individual can differ by twenty percent or more.

How this is calculated

Method and background

This is what the calculation gives for the numbers you entered. It is an estimate, not advice, and it knows nothing about your situation beyond those numbers. Rules for United States change on a published schedule; the effective date is shown on every rule-based tool.

How this is calculated

A MET is a multiple of resting metabolic rate, defined as 3.5 millilitres of oxygen per kilogram per minute. Multiplying by body mass and duration gives energy expenditure. The distinction that matters for anyone tracking a deficit is gross against net: an hour of running at 600 kcal includes roughly 70 kcal you would have burned sitting on the sofa, so counting the gross figure double-counts your resting metabolism. MET values are population averages and individual efficiency varies substantially.

a MET is a multiple of resting metabolic rate, taken as 3.5 ml of oxygen per kg per minute

m: Body mass in kg
t: Minutes

Worked examples

Each of these is asserted on every build. If a change to the engine ever moved one of these answers, the build would fail before the page could print it.

45 minutes of running

Weight: 72 kg
Activity: running at 8 km/h
Duration: 45 minutes
Sessions a week: 4

Calories burned470.6

8.3 x 3.5 x 72 / 200 x 45

Open this example

sitting at a desk is barely above resting

Weight: 72 kg
Activity: sitting at a desk
Duration: 60 minutes
Sessions a week: 5

Calories burned113.4

boundary: 0.5 METs above resting

Open this example

Method and limits

What it assumes

Standard MET values, which assume average efficiency and no adaptation.

What it deliberately does not model

MET tables assume a reference person and error on an individual is often twenty percent or more.
Fitness improves efficiency, so a trained person burns less for the same work.
Wearable estimates use different methods again and rarely agree with this.

Formula version 1.0.0 · definition 1.0.0 · United States · Report a problem with this calculator

Frequently asked questions

Why is the net figure lower?: Because you burn calories at rest anyway. Counting the gross figure against a diet deficit double-counts your resting metabolism for the duration of the workout.
Why does my watch disagree?: Wearables estimate from heart rate and their own models. Neither figure is measured; both are estimates from different assumptions.