Calorie Calculator
How it works
The resting figure comes from the Mifflin-St Jeor equation: BMR = 10 × kg + 6.25 × cm − 5 × age + s, where s is +5 for male and −161 for female. Weights in pounds and heights in inches are converted to kilograms and centimetres first, because that is the form the equation is defined in.
Daily calories are that BMR multiplied by an activity factor — 1.2 sedentary, 1.375 light, 1.55 moderate, 1.725 active, 1.9 very active. The factor is the loosest part of the estimate, so the table lists all five rather than just the one selected.
The figures either side of maintenance are plain arithmetic on the total: 250 and 500 kcal a day taken off it or added to it. They describe the offset, nothing more — the equation has no way of knowing anything about a particular body beyond the four numbers it was given.
For the weight-against-height figure instead, see the BMI calculator, which reads the same weight and height on a different scale.
Frequently asked questions
What is the difference between BMR and TDEE?
BMR is the energy the equation estimates a body uses at complete rest — breathing, circulation, keeping warm. TDEE is that figure multiplied by an activity factor, which stands in for everything done on top of resting: moving about, working, exercising.
Why do the activity levels differ so much?
The multipliers run from 1.2 to 1.9, so the top of the table is more than half again the bottom — and which one applies is a self-assessment, not a measurement. That spread is the main uncertainty in the estimate, which is why every level is listed rather than only the one selected.
Is this medical advice?
No. These are estimates from a population equation that knows four things about you, so they cannot account for your health, medication or how you actually live. A doctor or a registered dietitian is the person to talk to about what they mean for you.