Calorie and macro calculator

Find out how many calories a day you need to lose, maintain or gain weight, plus how much protein, fat, carbs and fiber to aim for. Enter your details and the numbers update as you type.

How it works

Your calorie needs depend on your age, sex, height, weight and activity [1].

The calculator first estimates your resting energy use with the Mifflin–St Jeor equation [2]. In a systematic review, this equation predicted resting metabolic rate within 10% for more people than other common equations [3]. It then multiplies that by your activity level to get maintenance calories, also called total daily energy expenditure (TDEE), and adds or subtracts calories for your goal.

It’s still an estimate. Treat the result as a starting point, not a prescription.

How many calories should I eat to lose weight?

Start with the “lose slowly” goal, which is about 275 kcal a day below maintenance. The calculator won’t show a weight-loss target below 1,200 kcal a day for women or 1,500 kcal for men. Going lower than that should be supervised by a doctor.

Expect faster progress in the first few weeks and slower progress after that. As you lose weight you burn less, so the same deficit loses weight more slowly over time [4]. Losing weight covers the rest.

How to use the number

1. Eat around the target for 2–3 weeks.
2. Weigh yourself a few mornings a week and look at the weekly average, not single days.
3. If the trend doesn’t match your goal, adjust by 100–200 kcal a day and repeat.

Your own trend is more accurate than any formula.

How much protein do I need?

The guidelines suggest 1.2–1.6 g of protein per kg of body weight per day [1]. The calculator uses 1.6 g when you’re losing or gaining and 1.2 g when you’re maintaining, and caps protein at 35% of your calories.

Macro ranges for adults

The long-standing reference ranges are 45–65% of calories from carbohydrate, 20–35% from fat and 10–35% from protein [5]. Fiber: about 25 g a day for women and 38 g for men [5].

The lower-carb and keto options in the calculator go below the carbohydrate range. Many people eat this way. If you have diabetes, kidney disease, are pregnant or take medication, check with your doctor first.

Next steps

• Weight loss calculator: when you could reach your goal weight.
• Meal prep planner: turn these numbers into a week of meals.
• What a normal day of eating looks like: the short version of the dietary guidelines.
• Recipes: every recipe lists calories, protein, fat, carbs and fiber per serving, so you can hit your numbers.

General information, not medical advice. If you have a health condition, are pregnant or take medication, check changes with your doctor.