CALCULATOR
Full Plan Calculator
Stats in, complete daily plan out: TDEE, calories, protein, and the cheapest way to close the gap.
Mifflin-St Jeor equation · General guidance, not medical advice.
Your full plan is below. Change goal or stats any time:
Daily Facts
Full plan · —
TDEE via Mifflin-St Jeor x activity. Protein at 1.4-1.9 g/kg by goal. Adjust with real-world results.
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How the Full Plan calculator works
Most calculators stop at one number. This one chains four steps: it estimates the calories you burn per day, applies your goal to set a calorie target, sets a protein target from your bodyweight, then subtracts what you already eat to show the gap you actually need to close.
Your energy burn is estimated with the Mifflin-St Jeor equation, which most dietetics bodies favour for the general population, multiplied by an activity factor from 1.2 (mostly sitting) to 1.725 (hard training). Fat loss applies a 20% reduction, muscle gain a 10% surplus.
Protein is set per kilogram of bodyweight rather than as a flat number, because a 55 kg person and a 100 kg person have genuinely different needs. Fat loss uses the higher end of the research range to protect muscle in a deficit.
The equations behind the numbers
Three equations are commonly used to estimate basal metabolic rate, the energy your body uses at complete rest. Mifflin-St Jeor, introduced in 1990, is considered the most accurate for the general population and is the one this calculator uses. The revised Harris-Benedict equation is older and tends to read slightly higher. Katch-McArdle works from lean body mass instead of total weight, which makes it more accurate for lean people who know their body fat percentage, and unusable for everyone else.
Women: BMR = 10W + 6.25H - 5A - 161
Women: BMR = 9.247W + 3.098H - 4.330A + 447.593
W is bodyweight in kilograms, H is height in centimetres, A is age in years and F is body fat as a decimal. BMR is then multiplied by an activity factor to give total daily energy expenditure, the calories you burn across a normal day.
Activity multipliers
| Activity level | Description | Multiplier |
|---|---|---|
| Sedentary | Desk work, little or no exercise | 1.2 |
| Light | Light exercise 1-3 days per week | 1.375 |
| Moderate | Exercise 3-5 days per week | 1.55 |
| Active | Hard exercise 6-7 days per week | 1.725 |
| Very active | Physical job or twice-daily training | 1.9 |
Turning your burn into a target
A kilogram of body fat stores roughly 7,700 kcal, so a daily deficit of about 550 kcal produces around half a kilogram of fat loss per week in theory. This calculator applies a 20 percent reduction for fat loss and a 10 percent surplus for muscle gain, which scales the change to your body size instead of applying the same blunt 500 kcal to everyone.
Very aggressive deficits are counterproductive. Cutting more than about 1,000 kcal per day, or losing more than roughly 1 percent of bodyweight per week, increases muscle loss, degrades training quality and is hard to sustain. Slower almost always wins over a year.
Calorie targets by goal, for an 80 kg moderately active adult
| Goal | Adjustment | Example daily calories | Expected rate |
|---|---|---|---|
| Fat loss | -20% | About 2,120 kcal | 0.5-0.75 kg per week |
| Maintenance | 0% | About 2,650 kcal | Stable |
| Muscle gain | +10% | About 2,915 kcal | 0.25-0.5 kg per month |
Protein: the part most calculators treat casually
Calories decide whether you gain or lose weight. Protein decides how much of that change is muscle rather than fat. In January 2026 the Dietary Guidelines for Americans raised the general-population recommendation from 0.8 to 1.2-1.6 g per kilogram, and sports-nutrition guidance for people training or dieting runs higher still.
| Situation | Protein per kg | 80 kg example |
|---|---|---|
| Sedentary, general health | 1.2-1.6 g | 96-128 g |
| Training 2-4x per week | 1.4-1.8 g | 112-144 g |
| Fat loss, keeping muscle | 1.6-2.2 g | 128-176 g |
| Body recomposition | 2.0-2.2 g | 160-176 g |
Protein in common foods
| Food | Serving | Protein |
|---|---|---|
| Chicken breast, cooked | 100 g | 31 g |
| Beef, lean, cooked | 100 g | 26 g |
| Canned tuna, drained | 100 g | 25 g |
| Salmon, cooked | 100 g | 25 g |
| Whey protein | 1 scoop (30 g) | 24 g |
| Greek yogurt or skyr | 170 g | 17 g |
| Cottage cheese | 100 g | 11 g |
| Lentils, cooked | 100 g | 9 g |
| Milk | 250 ml | 8 g |
| Egg | 1 large | 6 g |
How to use the result
- Hold the calorie and protein targets for two to three weeks without changing anything else.
- Weigh yourself under consistent conditions, first thing in the morning, and judge by the weekly average rather than any single reading.
- If weight is not moving in the direction you want after three weeks, adjust calories by about 10 percent and hold again.
- Keep protein constant while you adjust calories. It is the variable protecting your muscle.
- Add resistance training before adding cardio. Cardio burns calories; lifting decides what kind of tissue you keep.
Frequently asked questions
Is a TDEE estimate accurate?
Why does it ask what I already eat?
Should I eat the same calories every day?
Do I need supplements to hit the numbers?
Sources
- Mifflin MD et al. A new predictive equation for resting energy expenditure in healthy individuals. American Journal of Clinical Nutrition, 1990.
- Jager R et al. ISSN Position Stand: protein and exercise. JISSN, 2017.
- Frankenfield D et al. Comparison of predictive equations for resting metabolic rate in healthy nonobese and obese adults. Journal of the American Dietetic Association, 2005.
- Dietary Guidelines for Americans, 2025-2030. dietaryguidelines.gov
- National Institutes of Health, Office of Dietary Supplements. Nutrient fact sheets. ods.od.nih.gov
- NHS. Nutrition and health guidance. nhs.uk
- US Departments of Agriculture and Health and Human Services. Dietary Guidelines for Americans, 2025-2030. dietaryguidelines.gov
More tools: all calculators · Full Plan · Recomp · Body fat · Macros · Cheapest whey per 20 g
General information, not medical advice. Consult a qualified professional before changing your diet, especially with a medical condition.