Nutrition calculators
Five free calculators, each with the formula written out and its scientific source: calories, deficit, protein, BMI and water.
Which nutrition calculators are here?
Each calculator has its own page, with a worked example, a table, the limits of the formula and common questions.
- Daily calorie needsHow many calories you burn a day (BMR and TDEE, Mifflin-St Jeor formula) and what target to set to lose weight, maintain or gain.Open the calculator
- Calorie deficit and weight-loss paceChoose how many kilograms a week you want to lose and get your daily deficit, how many calories to eat and how long it takes to reach your goal weight.Open the calculator
- Protein needsHow many grams of protein you need a day for your weight, activity and goal, from the EFSA minimum of 0.83 g/kg up to the values for athletes.Open the calculator
- BMI (body mass index)Calculate your BMI from weight and height and see the WHO category, plus the weight range with a normal BMI for your height.Open the calculator
- Water intakeHow much to drink a day based on your weight (35 ml per kilogram), adjusted for exercise, pregnancy and breastfeeding.Open the calculator
How accurate are these calculators?
The calculators give estimates for healthy adults, not measurements: a person’s real needs can be about 10% above or below the formula.
We use the formulas with the strongest scientific support (Mifflin-St Jeor for metabolism, the WHO cut-offs for BMI, the EFSA reference values for protein and water) and list the source under every calculator.
The best test is your own log: if your weight has not moved in the direction you want after 2–3 weeks, adjust the target by 100–200 kcal or talk to a dietitian.
How should you use the results?
Start with your calorie needs, pick a weight-loss pace in the deficit calculator and set your protein for your goal.
Then log what you eat for a few weeks: only then will you know whether the estimate fits your body.
The result is an estimate for healthy adults. It does not replace advice from a doctor or dietitian, especially during pregnancy, with chronic conditions or eating disorders.
The number is only the start. Track it every day.
In Rod you set your target once, then see at every meal how much of your calories, protein and water you have had, with foods from Romanian shops.
