Calorie Deficit

Your BMR is what your body burns at rest, from the Mifflin-St Jeor formula: 10 × kg + 6.25 × cm − 5 × age, plus 5 for men or minus 161 for women. That is why it asks your sex and age. US heights and weights are converted first (1 in is 2.54 cm, 1 lb is 0.45359237 kg).

Your TDEE is what you burn in a day once activity is counted: BMR times 1.2 if you are mostly sitting, 1.375 for exercise 1 to 3 days a week, 1.55 for 3 to 5 days, 1.725 for 6 or 7 days, and 1.9 for very hard exercise every day or a physical job.

The deficit is what it takes to lose your chosen amount: about 7,700 kcal per kg (3,500 per lb), spread over seven days, so 0.5 kg a week is 550 kcal a day and 1 lb a week is 500. What to eat is your TDEE minus the deficit.

Two limits keep the suggestion safe. It never suggests less than 1,200 kcal a day for women or 1,500 for men, the usual floor for eating without medical support; when your plan would go lower, it stops at the floor and says so. And it never plans to lose more than 1% of your weight a week.

The time to your goal assumes the same deficit all the way. As you lose weight you burn a little less, so it usually takes longer; work it out again every few kilos. Formulas like this one are within about 10% for most people, and your own results over a few weeks are the better guide.

This is not medical advice, and it is not meant for children, teens, pregnancy or breastfeeding. What you type is saved on this device so you can come back to it. Clear all empties it, and Undo brings it back.