Krill KitsKrill Kits// A swarm of small, sharp tools for letters, numbers, and units.
§ 01 / TOOL

3,500 kcal · Gaining.

STATUS ACTIVEUNIT 4-4-9LATENCY <1MS
> INPUT
DAILY CALORIES
kcal
GOAL

DAILY MACROS.

PER DAY
// SPLIT
3,500 kcal · 25/50/25
// PROTEIN
219g
25% of kcal875 kcal
// CARBS
438g
50% of kcal1,750 kcal
// FAT
97g
25% of kcal875 kcal
// FORMULA
3,500 kcal × 25/50/25 (gain) = 219P · 438C · 97F
At 3,500 kcal/day with a gaining split (25/50/25), eat 219g protein, 438g carbs, and 97g fat per day.
§ 02 / ABOUT

How to use this.

Macronutrients — protein, carbs, and fat — are the three components every calorie is made of. Protein and carbs are 4 kcal per gram; fat is 9 kcal per gram. The number you eat each day is the sum. How you split those three matters: the same calorie total produces very different body composition, energy, and performance outcomes depending on the ratio.

This calculator takes a daily calorie target and splits it into grams of each using goal-specific ratios that most nutrition coaches use as starting points. If you don’t know your calorie target, run it through the TDEE calculator first.

// THE THREE SPLITS

  • LOSE · 40/30/30 — protein-forward to preserve muscle in a calorie deficit. Going lower on protein during a cut is where most diet regain comes from.
  • MAINTAIN · 30/40/30 — balanced. Works for most adults who aren’t pushing a specific goal.
  • GAIN · 25/50/25 — carb-forward to fuel higher training volumes and recovery. Protein percentage is lower but grams are higher because total calories are higher.

// HOW TO ACTUALLY TRACK IT

Use a food-tracking app — MyFitnessPal, Cronometer, or MacroFactor are the standards. Log what you eat, aim within ±10 grams of each target, don’t sweat a bad day. Consistency over weeks beats perfect adherence over days.

// WHEN TO ADJUST

Re-run the calculator whenever your calorie target changes — when you lose/gain 10–15 lbs, change activity levels, or shift goals. The ratios stay the same unless you change goals; only the total moves.

§ 03 / FAQ

Questions. Answered.

What are macros?+
Macronutrients — the three energy-providing components of food. Protein and carbs contain 4 kcal per gram; fat contains 9 kcal per gram. Your daily calorie target is a sum of these three, and how you split them affects body composition, performance, and satiety. This calculator takes your calorie target and splits it into goal-appropriate grams.
Why should I track macros instead of just calories?+
Because calories only tell half the story. 2,000 calories from protein and vegetables produces very different body composition than 2,000 from sugar and fat, even though the scale reads the same. Macro targets protect muscle in a deficit, fuel training in a surplus, and keep you full enough to stick to the plan.
What do the ratios mean?+
Lose (40/30/30) is protein-forward to preserve muscle while in a calorie deficit. Maintain (30/40/30) is a balanced split that works for most adults not pushing a specific goal. Gain (25/50/25) is carb-forward to fuel higher training volumes. These are starting points — adjust based on how you respond over 2–3 weeks.
How accurate are these splits?+
As starting points, very. As prescriptions for your body, directionally correct within ±5–10%. Protein needs scale with muscle mass and training volume; fat needs bump up with hormonal considerations; carbs fluctuate with activity. Use the numbers, then refine based on what your energy, recovery, and physique actually do.
Should protein be even higher for fat loss?+
Possibly. Many coaches push protein to 1.0–1.2 grams per pound of body weight (not calorie percentage) during aggressive cuts, because muscle retention is the whole game. That can work out to 40–50% of calories at low intakes. Use this calculator as a floor, not a ceiling.
What do I do with the grams?+
Hit them, roughly, every day. Use a food-tracking app (MyFitnessPal, Cronometer, MacroFactor) or a notebook. Aim within ±10g of each target. Perfect adherence isn’t required — consistency over weeks is.
Do I need to recalculate as I lose weight?+
Yes — but start with the calorie side. When your TDEE drops, rerun it and feed the new number into this calculator. Ratios stay the same unless you change goals.
§ 04 / TOOLS

Related calculators.

§ 05 / READING

Deeper dives.

Macros for 3,500 kcal · Gaining · Krill Kits