Discover your number.

It’s the calories the person you want to be eats in a day. Eat it from today, and your weight comes down to meet it, then stays there. No diet to finish, and nothing to come off.

About you

Sex

The formula differs for men’s and women’s bodies.

45
5 ft 10 in
220 lb
180 lb
Your everyday life

How you live now, not workouts you’d add. The number fits the life you actually lead.

Your number

2,450kcal a day

What the 180 lb you eats to stay at 180 lb.

  • You eat 2,450
  • Your body covers 330

Weight to go
40 lb
At first
0.7 lb a week
Resting burn today
1,980 kcal
Resting burn at your goal
1,780 kcal
Find your real number in the beta

Where eating it takes you

Your projected weight if you eat 2,450 every day.

After 2 years
191 lb
Down by then
29 lb

Along the way

How farWeightWhen
How this is worked out

Your resting burn comes from the Mifflin-St Jeor equation, using your sex, age, height and weight. Multiplying it by your everyday activity gives what a body burns in a day. Your number is that figure for the weight you want to be, rounded to the nearest 50.

Each day you eat it, your body covers the difference between its burn and your number from what it carries, at about 7,700 kcal per kilogram (3,500 per pound). As your weight falls, your burn falls with it and the difference shrinks, so the curve flattens and approaches your goal rather than arriving on a set date.

Real bodies vary. Water, muscle and how carefully food is counted all move the line, and formulas like this are often 10 to 15 percent out for any one person. It’s a starting estimate, not medical advice.

Then find your real number

A formula gets you started. The app finds the number your body actually runs on, from what you eat and what the scale says, and keeps it up to date as your life changes.

  1. Say what you’re eating. Tap your Apple Watch and say it. The calories are worked out for you, in seconds.
  2. Weigh in each morning. Your Withings scale sends the reading on its own.
  3. Your number, from your own life. After about two weeks of both, the number is worked out from your own food and weight, not a formula, and it moves when your life does.