40/30/30 Macro Calculator
The Zone-diet-style split -- 40% carbs, 30% protein, 30% fat -- in real grams.
Daily calories for maintain weight
2668 cal
Protein
200g
Carbs
267g
Fat
89g
Worked example, step by step
Two reference people, run through exactly the same formulas as the calculator above. Swap in your own numbers and the steps are identical.
Alex
Male · 30 · 5'9" · 170 lb · moderately active
- Weight
- 170 lb × 0.4536
- 77.1 kg
- Height
- 5'9" = 69 in × 2.54
- 175.3 cm
- BMR
- 10 × 77.1 + 6.25 × 175.3 − 5 × 30 + 5
- 1,721 cal
- TDEE
- 1,721 × 1.55 (moderately active)
- 2,668 cal
2,668 cal as 40/30/30
| Carbs | 40% of 2,668 ÷ 4 | 267 g | 40% |
| Protein | 30% ÷ 4 | 200 g | 30% |
| Fat | 30% ÷ 9 | 89 g | 30% |
Sam
Female · 30 · 5'5" · 140 lb · lightly active
- Weight
- 140 lb × 0.4536
- 63.5 kg
- Height
- 5'5" = 65 in × 2.54
- 165.1 cm
- BMR
- 10 × 63.5 + 6.25 × 165.1 − 5 × 30 − 161
- 1,356 cal
- TDEE
- 1,356 × 1.375 (lightly active)
- 1,864 cal
1,864 cal as 40/30/30
| Carbs | 40% of 1,864 ÷ 4 | 186 g | 40% |
| Protein | 30% ÷ 4 | 140 g | 30% |
| Fat | 30% ÷ 9 | 62 g | 30% |
Maintaining weight, so the calorie target is the TDEE itself; a cut or bulk would subtract or add its adjustment first.
What the activity levels actually mean
The multiplier is where most people go wrong, usually by picking a level too high. A desk job plus three gym sessions a week is "lightly active", not "moderately active" -- the gym hour is real, but the other 23 are sitting. Here is Alex's TDEE at every level, from the same 1,721-calorie BMR:
| Level | Who it fits | Multiplier | Alex's TDEE |
|---|---|---|---|
| Sedentary | Little to no exercise, desk job | × 1.2 | 2,066 cal |
| Lightly active | Light exercise 1-3 days/week | × 1.375 | 2,367 cal |
| Moderately active | Moderate exercise 3-5 days/week | × 1.55 | 2,668 cal |
| Very active | Hard exercise 6-7 days/week | × 1.725 | 2,970 cal |
| Extra active | Very hard exercise and a physical job | × 1.9 | 3,271 cal |
The gap between sedentary and very active is 904 calories a day for the same person -- more than a whole meal. When in doubt, pick the lower level and let the two-week weigh-in correct you.
Gram targets by calorie level
With a percentage split every macro scales with calories, so the table is the same for everyone at a given calorie level -- your bodyweight only decides which row you land on.
Gram targets assume you weigh food. If a recipe is in cups and tablespoons, CookSubs converts cups to grams by ingredient so the number you log matches the number here.
| Calories | Protein | Carbs | Fat |
|---|---|---|---|
| 1,600 | 120 g | 160 g | 53 g |
| 1,800 | 135 g | 180 g | 60 g |
| 2,000 | 150 g | 200 g | 67 g |
| 2,200 | 165 g | 220 g | 73 g |
| 2,500 | 188 g | 250 g | 83 g |
| 2,800 | 210 g | 280 g | 93 g |
| 3,200 | 240 g | 320 g | 107 g |
After two weeks: how to adjust
Every number on this page is an estimate of the average person with your stats. You are not the average person, and the only way to find your real number is to eat at the estimate and watch the scale. The rules that make that work:
- Weigh daily, judge weekly. Same scale, same time, after the bathroom, before food. Daily readings swing 2-4 lb on water alone; compare weekly averages, not days.
- Give it 14 days. The first week of any change is mostly water and glycogen. The second week is the first honest read.
- Then move 100-200 calories, not 500. Trending down when you meant to hold? Add 100-200. Trending up? Subtract 100-200. Small moves, then another two weeks.
- Recalculate when your weight changes by 10-15 lb. Your BMR moves with your bodyweight, so a target set months ago is stale.
- Keep protein fixed, flex carbs and fat. Protein is the one macro tied to keeping muscle; it is the last thing to cut and the first to hit.
Common mistakes
- Counting the workout twice. The activity multiplier already includes your training. Adding the calories your watch says you burned on top of it double-counts, often by 300-600 a day.
- Treating the number as exact. Mifflin-St Jeor is accurate to within about 10% for most healthy adults. For Alex that is a 267-calorie band either side of 2,668.
- Eating at BMR. BMR is what you burn asleep and fasting. Eating that little for long is a crash diet with a scientific-sounding name; the deficit belongs under TDEE, not under BMR.
- Rounding macros to the gram. Food labels are legally allowed to be 20% off. Hitting protein within 10-15 g and calories within 100 is precise enough; anything tighter is false accuracy.
Keep going
- For a much lower carb share than 40/30/30, the keto calculator drops carbs to roughly 5% of the same calorie target instead. Keto Macro Calculator
- 40/30/30 caps protein at 30% of calories; the high-protein calculator sets a bodyweight-based target that can run higher for a lifter. High-Protein Macro Calculator
Frequently Asked Questions
Where does the 40/30/30 split come from?
It's the ratio popularized by the Zone diet -- 40% of calories from carbs, 30% from protein, and 30% from fat -- meant to be a more moderate middle ground than very-low-carb or very-high-carb approaches.
Is 40/30/30 better than a bodyweight-based protein target?
Not objectively better, just different -- a percentage split keeps the same ratio no matter your calorie target, while a bodyweight-based target keeps protein consistent as calories change. Neither is wrong; it depends what you're trying to hold steady.
Can I use this split for any goal?
Yes -- the percentages stay the same whether you're cutting, bulking, or maintaining, since your goal changes total calories, and this just splits whatever that number is into 40/30/30.
Is 40/30/30 good for fat loss?
It is a reasonable default, mainly because 30% protein is higher than most people eat, which helps fullness and muscle in a deficit. On a big cut the percentage can undershoot: 30% of 1,500 calories is 112 g, which is low for a heavier person. If you are over about 180 lb and cutting, check the protein gram number against 0.8-1 g per pound and raise it if needed.
What does 30% protein look like on a plate?
For a 2,000-calorie day, 150 g of protein is roughly: two eggs and Greek yoghurt at breakfast (35 g), a chicken breast at lunch (45 g), a palm-sized portion of fish or beef at dinner (40 g), and a scoop of whey or cottage cheese somewhere (30 g). The 40% carbs is about 200 g -- two cups of cooked rice plus fruit and vegetables gets there.