THE MACRO CALCULATOR
Calories, protein, carbs, and fat — calculated with the Mifflin-St Jeor equation, the same math our in-app Coach uses. Fill in five fields and get numbers you can actually train on.
THE CALCULATOR
How the math works
The calculator uses the Mifflin-St Jeor equation, which validation studies have repeatedly found to be the most accurate of the common BMR formulas for the general population:
BMR (women) = 10 × kg + 6.25 × cm − 5 × age − 161
TDEE = BMR × activity multiplier (1.2 – 1.9)
Then your goal sets the calorie target: a cut takes 20% off TDEE (steady fat loss without wrecking training), a bulk adds 10% (muscle with minimal spillover), and maintain is TDEE straight.
How the macros are split
- Protein: 1g per pound of body weight. The research consensus for people who train lands between 0.7–1g/lb; we set the simple, memorable top of that range. Protein protects muscle in a deficit and builds it in a surplus.
- Fat: 25% of calories. Enough for hormones and satiety, low enough to leave room for training fuel.
- Carbs: everything left. Carbs fill the remaining calories because they're your training fuel — and the flexible lever you can move meal to meal.
- Fiber: aim for 28g+. Not in the headline table, but the app tracks it daily, because it's the quietest predictor of how good your diet actually is.
Why any calculator is only a starting point
Every TDEE formula — this one included — has an error bar of a couple hundred calories, because it can't see your genetics, your job, or how much you fidget. The calculator gives you a smart starting line, not gospel.
The fix is to let your own data correct the estimate. That's what the Coach inside EatSleepRep does: after ten days of food logs and a handful of weigh-ins, it computes your actual energy burn from your intake and your weight trend (the same energy-balance math coaches charge for), and offers updated targets weekly. A formula guesses; your logbook knows.
The rest of the free calculators — barbell plate math and a one-rep max estimator — are on the tools page, and none of them ask for an email.
Open the free tracker and let the Coach dial you in →FAQ
Which macro calculator formula is most accurate?
Mifflin-St Jeor is the best-validated general-purpose equation, which is why we use it here and in the app. Katch-McArdle can edge it out if you know your body-fat percentage accurately — most people don't.
How much protein do I need to build muscle?
0.7–1g per pound of body weight per day covers the research range for trainees. We default to 1g/lb because it's simple, satiating, and protective in a deficit.
Should I eat back exercise calories?
No — the activity multiplier already includes your training. Eating back exercise calories on top double-counts them, which is the most common reason "the math doesn't work."
How fast should I expect to lose or gain?
On these defaults: a cut trends around 0.5–1% of body weight per week; a lean bulk around 0.25–0.5%. If your two-week trend is off, adjust calories by ~150–200 and reassess — or log in EatSleepRep and let the Coach do exactly that for you.