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Calorie & Protein Calculator

This calculator gives a general starting estimate of how many calories your body uses in a day and a common protein range for active adults. It uses a widely used formula (Mifflin-St Jeor) and standard activity levels. It is a rough guide for healthy adults, not a diet plan. If you have a health condition, are pregnant or under 18, talk to a doctor or dietitian.

How it works

• BMR (Mifflin-St Jeor) = 10 × weight kg + 6.25 × height cm − 5 × age, then +5 (male formula) or −161 (female formula)
• Maintenance = BMR × activity factor (1.2 to 1.9)
• Gentle loss = maintenance − 10-15%; gentle gain = maintenance + 10%
• Protein = 1.2-1.6 g per kg of body weight, a common range for active adults (0.8 g/kg is the general minimum for adults)

Three things this tool can't see

• Your body. Formulas can be off by 10% or more for any one person. Track how you feel and adjust slowly.
• Health conditions. Kidney problems, diabetes, pregnancy and medicines change what is right for you. Ask a doctor or dietitian.
• Food quality. Calories are not the whole story. Plenty of vegetables, fibre and water matter too.

This tool gives general information only and is not medical or nutrition advice. Check with a doctor before starting exercise or changing your diet. We make no health or performance claims. Some links on this site may earn us a commission. Read our disclosure.