Calculator Inputs
Example Data Table
| Profile | Sex | Age | Weight | Height | Activity | Goal | Estimated Maintenance | Target Calories |
|---|---|---|---|---|---|---|---|---|
| Example A | Male | 29 | 78 kg | 178 cm | Moderately Active | Moderate Deficit | 2,730 kcal | 2,230 kcal |
| Example B | Female | 34 | 64 kg | 168 cm | Lightly Active | Lean Surplus | 2,040 kcal | 2,240 kcal |
| Example C | Male | 41 | 92 kg | 182 cm | Very Active | Maintain | 3,280 kcal | 3,280 kcal |
Formula Used
1) Mifflin-St Jeor BMR
Male: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) + 5
Female: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) − 161
2) Katch-McArdle BMR
BMR = 370 + (21.6 × lean body mass in kg)
3) Base TDEE
Base TDEE = BMR × activity multiplier
4) Full Maintenance Estimate
Maintenance Calories = Base TDEE + planned exercise calories + thermic effect calories
5) Target Calories
Target Calories = Maintenance Calories + daily calorie adjustment
6) Weekly Weight Change
Weekly change in kg = (daily adjustment × 7) ÷ 7,700
7) Macro Targets
Protein calories = protein grams × 4
Fat calories = fat grams × 9
Carb calories = remaining calories after protein and fat
How to Use This Calculator
- Choose your unit system, sex, age, weight, and height.
- Enter body fat percentage if you know it.
- Select a BMR formula or keep auto selection.
- Choose your daily activity level.
- Add planned exercise calories and thermic effect percentage.
- Pick a preset surplus or deficit, or enter a custom adjustment.
- Select protein strategy and fat percentage.
- Set the projection length in weeks.
- Press calculate to see maintenance calories, target calories, macros, and projected weight trend.
- Use the CSV or PDF buttons to export your results.
FAQs
1) What is a calorie deficit?
A calorie deficit means eating fewer calories than your body burns. It is commonly used for fat loss. The calculator estimates a safe deficit and shows how it may influence weekly body weight.
2) What is a calorie surplus?
A calorie surplus means eating more calories than your body burns. It supports muscle gain and body weight increase. Smaller surpluses usually limit unnecessary fat gain better than aggressive surpluses.
3) Why does body fat percentage matter?
When body fat is known, the calculator can estimate lean mass and use Katch-McArdle. That often improves BMR accuracy for leaner or more muscular people.
4) Which BMR formula should I choose?
Use auto selection if unsure. Mifflin-St Jeor works well for most adults. Katch-McArdle can be more individualized when you have a realistic body fat estimate.
5) Are projected weekly changes exact?
No. Real progress varies with water balance, adherence, metabolism changes, training, sleep, and stress. Treat the chart as a planning estimate, not a guaranteed outcome.
6) How much protein should I eat?
Many active people do well between 1.6 and 2.2 grams per kilogram daily. Deficit phases often benefit from the higher end to support muscle retention.
7) Why include thermic effect and exercise calories?
They refine maintenance estimates. Food digestion uses energy, and structured exercise can materially affect daily expenditure. Including both can make calorie planning more realistic.
8) Can I use this for maintenance eating?
Yes. Choose the maintain option or set a custom adjustment of zero. The calculator will then estimate daily maintenance calories and provide supporting macro targets.