Skip to content
user@convertitive:~$convertitive

Macro Calculator (Protein, Carbs, Fat) — Daily Targets

Daily kcal plus grams of protein, carbs, and fat — divided across your meals.

Buğra SözeriHealth
Published
Reviewed by Convertitive Health Desk
Medical disclaimer: Macro targets are screening estimates, not a clinical prescription. People with diabetes, kidney disease, eating disorders, or any condition that requires medical nutrition therapy should work with a registered dietitian or physician rather than rely on a generic calculator.

A macro calculator starts from your TDEE — total daily energy expenditure — and splits that calorie target into grams of protein, carbohydrate, and fat. The BMR base uses the Mifflin-St Jeor equation (1990), the most accurate of the common predictive formulas for the general adult population per a 2005 American Dietetic Association review.

The goal modifier adjusts kcal: a 500 kcal/day deficit produces roughly 0.45 kg (1 lb) of fat loss per week; a 250 kcal/day surplus supports lean muscle gain without excessive fat. Protein and carbs supply 4 kcal/g; fat supplies 9 kcal/g.

Daily calorie target
2,662kcal / day

Based on TDEE of 2,662 kcal (maintenance).

Protein
200g / day
30% of kcal · 799 kcal · 4 kcal/g
Carbs
266g / day
40% of kcal · 1,065 kcal · 4 kcal/g
Fat
89g / day
30% of kcal · 799 kcal · 9 kcal/g
Per-meal split — 4 meals/day
Even distribution across meals
  • Meal 1
    666 kcal50P67C22F
  • Meal 2
    666 kcal50P67C22F
  • Meal 3
    666 kcal50P67C22F
  • Meal 4
    666 kcal50P67C22F

Formula: Mifflin-St Jeor (1990) BMR × activity factor, then goal adjustment. Macros derived from % of total kcal at 4 kcal/g (protein, carbs) and 9 kcal/g (fat). Estimates ±10%.

How to use

  1. Enter your stats

    Pick sex, units, then weight, height, and age. The calculator runs Mifflin-St Jeor BMR and applies your activity multiplier to get TDEE.

  2. Choose a goal

    Cut subtracts 500 kcal/day for steady fat loss. Maintain matches TDEE. Bulk adds 250 kcal/day — a slow gain that limits fat accumulation.

  3. Pick a macro split

    Balanced (30/40/30) suits most. Keto (25/5/70) for ketogenic dieters. High-protein (40/30/30) for muscle gain and cuts. Zone (30/40/30, Sears protocol) for the Zone diet.

  4. Divide per meal

    Toggle 3, 4, or 5 meals to see per-meal kcal and macros. Even splits work for most people; weight trainers often shift more protein to post-workout.

Macro split presets

PresetProtein / Carbs / FatBest for
Balanced30 / 40 / 30General health, weight maintenance
Keto25 / 5 / 70Ketogenic dieters, very-low-carb protocols
High-protein40 / 30 / 30Muscle gain, aggressive cuts, athletes
Zone (Sears)30 / 40 / 30Followers of the Zone diet protocol

Frequently asked questions

Why does protein recommendation vary so much?
Different goals demand different protein loads. Sedentary adults need ~0.8 g/kg; recreational lifters 1.4–1.8 g/kg; physique athletes in a cut 2.2–2.6 g/kg. A 40% split at a 2,200 kcal target gives 220 g protein — about 2.9 g/kg for a 75 kg lifter, well within the upper safe range.
Are these macro numbers precise?
Within roughly ±10% — same as the underlying TDEE estimate. The biggest source of error is overestimating activity. If the scale doesn't move in two weeks, adjust kcal by ±200 and recompute macros at the same split.
What about fiber and sugar?
This calculator doesn't break carbs into fiber vs sugar. Aim for 25–35 g fiber/day and keep added sugar under 10% of kcal per WHO guidance. Most of your carbs should come from whole grains, fruit, vegetables, and legumes.
How do I split macros across meals?
Even splits work for most people. If you train, place 30–40 g of protein within 1–2 hours after the session to maximize muscle protein synthesis. Skip-breakfast / intermittent-fasting protocols use 2–3 meals; bodybuilders often use 5–6.
Should I weigh food to hit macros exactly?
For the first 2–4 weeks, yes — most people drastically underestimate portions. Once you've internalized the look of 30 g protein or 50 g carbs, eyeballing within ±15% is fine for most goals. Competition prep is the exception.
What about supplements?
Whey or plant protein powder is a convenience, not a requirement. Creatine monohydrate (3–5 g/day) is the most evidence-backed performance supplement. Multivitamins fill gaps but don't compensate for a poor diet.
Why does the keto split use so little carb?
Ketosis — the metabolic state where the body burns ketones for fuel — typically requires keeping carbs under 20–50 g/day. At 2,000 kcal, 5% carbs = 25 g, which sits at the upper edge of ketogenic. Drop further if your blood ketones don't rise.

About

How the calorie target is built

Step 1: Mifflin-St Jeor BMR — Men: 10×kg + 6.25×cm − 5×age + 5; Women: same first three terms then −161. Step 2: BMR × activity multiplier (1.2 sedentary to 1.9 very active) = TDEE. Step 3: TDEE − 500 (cut), 0 (maintain), or +250 (bulk) = daily kcal target. Step 4: split kcal into protein/carbs/fat by the chosen %, then divide by 4 or 9 kcal/g for grams.

When to ignore the result

Pregnancy and lactation shift requirements significantly. Type-1 and insulin-dependent type-2 diabetes need carb counting matched to insulin dosing — not a generic split. Chronic kidney disease often requires protein restriction. Eating-disorder recovery should be supervised by a clinician. In all these cases the calculator's output is at best a rough starting point and at worst harmful.

Reading your own response

Weigh yourself on the same scale at the same time of day, 3–4 times per week, and average. If body weight doesn't shift in the expected direction after 14 days, adjust kcal by ±200 and hold the new target for another 14 days. Avoid daily adjustments — water-weight noise dominates short windows.

Sources & references

Authoritative references behind the math, constants, and tables on this page. Verified by Buğra Sözeri on the dates shown and re-checked at every deploy.