fituba

Daily calorie and macro calculator

Estimate how many calories you need a day to maintain, lose fat or build muscle at the pace you choose, with your protein, carb and fat split. Free, no account, right in your browser.

Your details

Fill in your details to see your estimate.

General estimate for adults. If you're pregnant, breastfeeding or under medical guidance, use your provider's goals. Everything is calculated in your browser: nothing is sent or saved.

How it's calculated

  1. Resting burn with the Mifflin–St Jeor equation: 10 × weight in kg + 6.25 × height in cm − 5 × age, plus 5 for men or minus 161 for women.
  2. Activity: multiplied by 1.25 if you mostly sit, 1.45 if you move and work out, or 1.65 if you're very active. The result is your estimated maintenance.
  3. Goal and pace: to lose fat, the deficit aims to lose 0.25%, 0.5% or 0.75% of your body weight per week (Gentle, Recommended or Fast), never more than 25% below maintenance. To build muscle it uses half that pace, up to 15% above. Lose fat and build muscle subtracts 5%; maintain keeps your maintenance. It uses 7,700 kcal ≈ 1 kg (about 3,500 kcal ≈ 1 lb) as a general guide.
  4. Unsupervised minimum: 1,200 kcal for women and 1,500 kcal for men, and never below your resting burn. If that minimum limits your goal, the calculator tells you.
  5. Macros: protein at 1.6 g per kg (if your BMI is over 25, based on the weight that matches a BMI of 25), fat at 30% of calories and the rest from carbs, at 4, 4 and 9 kcal per gram.
  6. Habits: 8,000 steps a day (6,000 from age 60) and strength training 2 days a week, or 3 if you want to build muscle.

Example: a 30-year-old woman, 143 lb (65 kg), 5'5" (165 cm), “I move and work out,” losing fat at the recommended pace.

Resting: 650 + 1,031 − 150 − 161 = 1,370 kcal. Maintenance: 1,370 × 1.45 ≈ 1,987 kcal. Pace: 0.5% of 65 kg = 0.325 kg (0.7 lb) per week ≈ 358 kcal less per day. Goal: 1,630 kcal · 104 g protein · 182 g carbs · 54 g fat, about −0.7 lb per week if she keeps it up.

Sample calculation with made-up data, not a recommendation.

What to do with your result

Treat it as a starting point. Log what you eat for 2 or 3 weeks and compare your weight trend with your goal; if needed, adjust your goals or review them with your dietitian. In Fituba you save these goals and see every day how many calories and how much of each macro you have left.

Limits of this calculator

FAQ

How many calories should I eat to lose weight?

It depends on your daily burn and the pace you choose. The calculator starts from your estimated maintenance and subtracts what it takes to lose 0.25%, 0.5% or 0.75% of your body weight per week, without going over a 25% deficit or below 1,200 kcal for women or 1,500 kcal for men. Watch your weight trend for a few weeks and adjust with your provider if needed.

Which pace should I pick?

Recommended, 0.5% of your body weight per week, is a sensible middle ground for keeping muscle if you train. Gentle goes slower and Fast needs a bigger deficit; none of them is a promise of results.

What is the Mifflin–St Jeor equation?

It's an equation published in 1990 that estimates resting energy expenditure from weight, height, age and sex. It's one of the most widely used for adults.

How much protein should I eat?

The calculator uses 1.6 g per kg (about 0.7 g per lb) as a general starting point for adults who train; if your BMI is over 25, it uses the weight that matches a BMI of 25. Your needs may differ depending on your health and your plan.

What is maintenance, or TDEE?

It's the calories you burn on a typical day, including your activity. If you eat close to that number, your weight tends to stay the same.

Sources: Mifflin et al., 1990 · NHLBI, practical guide · Helms et al., 2014 · Morton et al., 2018 · Paluch et al., 2022 · WHO 2020.

Fituba documentation · Who's behind it and editorial method ·