Disclaimer

Last updated 11 October 2026.

The calculators on Macros Calculator are not medical advice. They estimate calorie, macronutrient, protein and body fat figures from equations published in nutrition and exercise science. Those equations were built from groups of people, and any one person can differ from the prediction, often by 10% or more.

Who the calculators are for

The calculators are designed for healthy adults aged 18 and over. Don't rely on them, and speak to a doctor or registered dietitian first, if you:

• are pregnant or breastfeeding
• are under 18
• have, or have had, an eating disorder
• have diabetes, kidney disease, heart disease or another medical condition
• take medication that affects your weight, appetite or blood sugar
• are a competitive athlete with specialist needs

Safety limits we apply

• We warn when a daily calorie target falls below 1,200 kcal for women or 1,500 kcal for men. Intakes that low are hard to make nutritionally complete without supervision.
• We flag weight loss faster than about 1% of body weight a week.
• We flag goal weights below a BMI of 18.5.

Use the numbers as a starting point

Track your weight and how you feel for two to four weeks, then adjust. Stop and seek medical advice if you feel unwell, dizzy, or constantly exhausted, or if your relationship with food starts to worry you.

Accuracy

We test every formula and correct errors quickly when they are reported. If you find a mistake, please tell us.