Calorie and Macro Calculator
Estimate a practical daily target for calories, protein, carbohydrates and fat. Choose metric or US units and get an answer in seconds.
How this macro calculator works.
The calculator uses your age, height, weight and the sex input required by the Mifflin-St Jeor equation to estimate resting energy. It then applies your activity level and goal.
- Estimate basal metabolic rate from your body measurements.
- Multiply by an activity factor to estimate maintenance calories.
- Adjust calories for your goal and divide them into a practical macro starting point.
Use the result as a starting point
Track your real-world progress for two to four weeks. If your weight, energy or training does not move as expected, adjust gradually rather than making a large change overnight.
See what is on your plate with NutriLens.
Take a meal photo to estimate calories and macros, explore ingredients and compare food choices.
Use the calculator with confidence.
How to use your estimate
Enter your details, choose an activity assumption and review the result as a starting estimate. Changing an activity selection changes the calculation; it does not measure your actual daily energy expenditure. The suggested macro split is a calculation rule, not an individualized meal plan.
A target and a food scan answer different questions. The calculator estimates daily numbers, while NutriLens estimates what a meal contains. Read the calories-versus-macros guide to compare them on a consistent basis.
Food tracking and nutrition guides
NutriLens analyzes meal photos and provides estimated calories and macronutrients. Check the identified food and portion before using a result. Hidden ingredients and cooking methods can change the estimate.
Three useful starting points, chosen for this app. The full reading list is one click away.
Calories Per Serving vs Per Container: Read the Label
Calculate calories for a whole pack or the amount you ate. Four worked label examples, per-100g conversions and an as-prepared double-counting check.
Read the guide NutritionHow Accurate Is an AI Calorie Scanner? Check Your Meal Estimate
Check a photo calorie estimate against a matching label and weighed serving. See a worked calculation, a comparison worksheet and what a scan cannot verify.
Read the guide NutritionHow to Track Calories in Homemade Meals
Use an ingredient worksheet and a batch-to-portion calculation to estimate homemade meal calories, including mixed recipes and leftovers.
Read the guide