Find your calorie needs, your calorie deficit target, and a realistic timeline to your goal weight. Pick from Mifflin-St Jeor, Harris-Benedict, or Katch-McArdle. Free, no signup required.
Start with Mifflin-St Jeor. It was developed in 1990, it is the equation most dietitians reach for first, and it tends to be the most accurate from just height, weight, age, and sex. Harris-Benedict, first published in 1919 and revised in 1984, usually runs a little higher. Use it as a second opinion if your Mifflin number feels low.
Pick Katch-McArdle when you know your body fat percentage. It works from lean body mass instead of total weight, so it fits people who are leaner or more muscular than average, where the other two tend to underestimate. Without a body fat number the calculator falls back to Mifflin-St Jeor.
Every formula here is a population average, so treat the result as a starting point, not a verdict. Your real maintenance calories can differ by a few hundred either way. The only way to know your own number is to track weight and intake for a few weeks and watch how your body responds.
A calorie deficit means eating below your TDEE. Roughly 3,500 calories sits in a pound, so about 500 fewer per day works out to a pound a week. This calculator lets you set a pace from 0.25 to 2 pounds per week, and it will not return a target below 1,200 calories for women or 1,500 for men.
This calculator is for informational purposes only and isn't medical advice. Talk to a doctor or registered dietitian before making changes, especially if you have a medical condition or are pregnant. Calorie balance is the biggest lever for most people, but it isn't the only one: sleep, stress, hormones, medications, muscle mass, and water retention can all move the number on the scale independent of what you eat. Read the full medical disclaimer.