Keto Calculator

Fat (g) = target × fat% ÷ 9 · Protein (g) = target × protein% ÷ 4 · Carb (g) = target × carb% ÷ 4

target

The daily calorie target you intend to eat (kcal)

fat %

Fat share of the split you pick

protein %

Protein share of the split, checked against a floor

protein floor

The low end of the range for your weight and activity level (g/kg)

carb %

Carbohydrate share, 5 percent in all three splits

Use it once you have a calorie target you intend to eat — from the calorie calculator, or from a plan someone has given you. The output is in grams rather than shares, because grams are what a kitchen scale and a food label give you. If the badge says the protein is under the floor, there are two ways out: a split with more protein, or a higher calorie target. Both are on this page.

1. 2,000 kcal a day, 70 kg, moderately active, standard split

   1. Standard split: 70% fat, 25% protein, 5% carbohydrate
   2. Fat: 2000 × 0.70 ÷ 9 = 155.56, rounded to 156 g
   3. Protein: 2000 × 0.25 ÷ 4 = 125 g
   4. Carbohydrate: 2000 × 0.05 ÷ 4 = 25 g
   5. Floor for 70 kg at a moderate activity level: 70 × 1.2 = 84 g
   6. 125 g clears the 84 g floor, so the badge reads adequate

   The floor is the low end of the range, not a target — meeting it means the split is not short of protein, not that 84 g is what you should aim for. Judging against the top of the range instead would fail most ketogenic splits by construction.

2. 2,400 kcal a day, 80 kg, active, classic split

   1. Classic split: 75% fat, 20% protein, 5% carbohydrate
   2. Fat: 2400 × 0.75 ÷ 9 = 200 g
   3. Protein: 2400 × 0.20 ÷ 4 = 120 g
   4. Carbohydrate: 2400 × 0.05 ÷ 4 = 30 g
   5. Floor for 80 kg at an active level: 80 × 1.6 = 128 g
   6. 120 g falls under the 128 g floor, so the badge warns

   Raising the fat share is what lowers the protein, and heavier people need more protein — so the two effects compound. This is the case the page exists for: the three splits look like variations on a theme until the floor is applied and one of them lands short.

The comparison with public guidelines is a comparison, not a verdict. The reference ranges put carbohydrate at 45 to 65 percent of energy, fat at 20 to 35 and protein at 10 to 35; a ketogenic split sits outside the first two by definition, which is why this page never tells you your carbohydrate is too high. Trials that match calories and protein find weight loss on a ketogenic diet to be about the same as on other diets. The word classic also deserves separating from the medical diet of the same name: a 4:1 ketogenic diet, used under supervision for epilepsy, draws about 90 percent of its calories from fat, well past the 75 percent the dropdown here calls classic. It is a pattern used under supervision and usually for a period, not the long-term diet those ranges describe.

What is a keto calculator?

It converts a daily calorie target into grams of fat, protein and carbohydrate at a chosen ketogenic ratio. Grams are the useful unit because that is what a food label and a kitchen scale give you. This one also works out the protein floor implied by your body weight and activity level, so you can see whether the ratio you picked actually delivers enough.

What ratio should I use?

The standard split, at 70 percent fat and 25 percent protein, is the one most people start with, and it clears the protein floor for a wide range of body sizes. The classic 75 / 20 ratio is the one the older calculators used, and it leaves the least room for protein. The relaxed 65 / 30 split is the safest of the three on protein and the least deeply ketogenic. None of the three is a published recommendation — the names are conventions that travel between calculators, so pick by which one you can actually hold.

Why does this page warn about protein?

Because a ketogenic split sets protein as a share of calories, and shares fall when the fat share rises or the target drops. Protein needs, in contrast, scale with body weight and activity — so a large or active person on a low-calorie classic split can end up under the floor without any of the three numbers looking wrong on its own. The badge is what makes that visible.

How is this different from the protein calculator?

They answer the same question from opposite ends. The protein calculator starts from your body weight and activity level and gives a range per kilogram, which is how the requirement is actually established. This page starts from your calorie target and the ratio you chose, and produces whatever protein that happens to leave. When they disagree, the per-kilogram figure is the one with the evidence behind it — the ratio is a choice.

Is a ketogenic diet safe long term?

That is not settled, and it is not a question a calculator can answer. Short trials show weight loss similar to other diets when calories and protein are matched. Longer-term data are thin, and the pattern sits far outside the macronutrient ranges written for the general population. Conditions such as pregnancy, type 1 diabetes, kidney disease and a history of disordered eating make it a decision to take to a clinician rather than to a web page.

• Nutrition and Athletic Performance — joint position statement — Academy of Nutrition and Dietetics, Dietitians of Canada and American College of Sports Medicine, 2016
• Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids (Macronutrients) — Institute of Medicine — National Academies Press, 2005
• Optimal clinical management of children receiving dietary therapies for epilepsy: updated recommendations of the International Ketogenic Diet Study Group — Kossoff EH, et al. — Epilepsia Open, 2018