acalculator

What are my keto macros?

Let the keto calculator estimate your daily calories from your body, activity and goal, or type them in. Set your carbs in grams and your protein share; fat gets the rest.

Your numbers

Units
Sex
Multiplies your BMR by 1.2, 1.375, 1.55, 1.725 or 1.9.
250 calories a day for each 0.5 lb a week.
More options
BMR formula
Fat a day
128 g

At 1,927 calories a day, eat about 128 g of fat, 169 g of protein and 25 g of carbs.

Protein a day
169 g
Carbs a day
25 g
Calories a day
1,927
Fat share
59.8%
Protein share
35%
Carbs share
5.2%
Calories from fat
1,152
Calories from protein
674
Calories from carbs
100
Against keto ranges
All inside the usual keto ranges.

Fat a day: 128 g. At 1,927 calories a day, eat about 128 g of fat, 169 g of protein and 25 g of carbs.

Where do your keto calories come from?

This calculator gives general information only. It is not medical advice and does not replace a doctor or other health care provider. Talk with a professional about your results. Terms of use

How to calculate

Works out daily keto macros: a fixed number of grams of carbs, a share of protein and the rest as fat, from typed calories or from your BMR, activity and goal, checked against ketogenic diet ranges.

Example with the default inputs (Daily calories Work them out, Sex Female, Age 30, Height 5 ft 5 in, Weight 150 lb, Activity Light: exercise 1 to 3 days, Goal Keep my weight, Carbs (g a day) 25, Protein 35%, BMR formula Mifflin-St Jeor): At 1,927 calories a day, eat about 128 g of fat, 169 g of protein and 25 g of carbs.

Method: Carbs (g) as typed; protein (g) = calories × protein share ÷ 4; fat (g) = (calories − carbs × 4 − protein calories) ÷ 9. Calories are typed, or TDEE (BMR × activity factor) − the goal.

  • Protein and carbohydrate give 4 calories per gram and fat gives 9 (21 CFR 101.9).
  • The keto ranges are from StatPearls: 20 to 50 g of carbohydrate a day; about 55–60% of calories from fat, 30–35% from protein and 5–10% from carbohydrate.
  • Worked-out calories use Mifflin-St Jeor or the revised Harris-Benedict, the activity factors 1.2 to 1.9, and 500 calories a day per pound a week.
  • This is an estimate for planning, not medical advice; talk to a doctor before a ketogenic diet, especially with diabetes, kidney disease or pregnancy.

Machine-readable copies: Markdown, JSON.

Worked examples

Each example is checked against the calculator on every build.

  1. Daily calories Work them out, Sex Female, Age 30, Height 5 ft 5 in, Weight 150 lb, Activity Light: exercise 1 to 3 days, Goal Keep my weight, Carbs (g a day) 25,000 g, Protein 35,000 g, BMR formula Mifflin-St Jeor gives Calories a day 1,926.737388, Fat a day 128 g, Protein 169 g, Fat share 59.809879%, Against keto ranges All inside the usual keto ranges..Source: Masood W, Annamaraju P, Khan Suheb MZ, Uppaluri KR. Ketogenic Diet. StatPearls, 2023 (https://www.ncbi.nlm.nih.gov/books/NBK499830/, retrieved 2026-10-01); Mifflin et al. 1990; 4, 4 and 9 calories per gram (21 CFR 101.9)
  2. Daily calories Work them out, Sex Male, Age 35, Height 5 ft 10 in, Weight 180 lb, Activity Moderate: exercise 3 to 5 days, Goal Lose 1 lb (0.45 kg) a week, Carbs (g a day) 30,000 g, Protein 30,000 g, BMR formula Mifflin-St Jeor gives Calories a day 2,224.460212, Fat a day 160 g, Protein 167 g.Source: Mifflin et al. 1990; 500 calories a day for 1 lb a week (Wishnofsky 1958)
  3. Daily calories I know them, Calories a day 2,000, Carbs (g a day) 20,000 g, Protein 30,000 g gives Fat a day 147 g, Protein 150 g, Carbs share 4%, Against keto ranges Fat 66% is over the 55% to 60% range. Carbs 4% is under the 5% to 10% range..Source: Masood W et al. Ketogenic Diet, StatPearls 2023 (fat 55–60%, protein 30–35%, carbs 5–10%, carbs 20–50 g a day)

How it works

Daily calories. Type them (500 to 10,000), or let the calculator work them out:

  • BMR, Mifflin-St Jeor: 10 × kg + 6.25 × cm − 5 × age, + 5 for men, − 161 for women.
  • BMR, revised Harris-Benedict: men 88.362 + 13.397 × kg + 4.799 × cm − 5.677 × age; women 447.593 + 9.247 × kg + 3.098 × cm − 4.33 × age.
  • Daily calories = BMR × activity factor (sedentary 1.2, light 1.375, moderate 1.55, very active 1.725, extra 1.9), less 0, 250, 500 or 1,000 calories for keeping weight or losing 0.5, 1 or 2 lb a week (3,500 calories a pound).

Macros.

  • Carbs (g) = the grams you type; carb calories = carbs × 4.
  • Protein calories = calories × protein share ÷ 100; protein (g) = protein calories ÷ 4.
  • Fat calories = calories − carb calories − protein calories; fat (g) = fat calories ÷ 9.
  • Shares: fat and carbs as their calories ÷ daily calories × 100; protein as typed.

Grams and calories show as whole numbers and shares to 1 decimal, rounded half up for display; the maths runs in floating point.

Keto check. The line "Against keto ranges" lists, in this order: carbs outside 20 to 50 g a day ("Carbs x g are outside the 20 to 50 g a day"), then each share outside its range, compared at 1 decimal: fat 55% to 60%, protein 30% to 35%, carbs 5% to 10% ("Fat 66% is over the 55% to 60% range"). With none outside it reads "All inside the usual keto ranges."

Low-calorie note. With a loss goal, calories under 1,200 (women) or 1,500 (men) a day add a note; typed calories under 1,200 add it too.

Rules

  • Age 18 to 100; height at least 0.9 m; weight at least 25 kg.
  • Carbs from 0 to 300 g a day; protein from 0% to 100%.
  • When carbs and protein give more calories than the day's total, there is no answer: "Carbs and protein give x calories, more than the y a day. Lower one of them."
  • When a loss goal takes more calories than you burn, there is no answer: "This goal takes more calories a day than the x you burn."

Worked examples by hand

A 30-year-old woman, 5 ft 5 in (165.1 cm), 150 lb (68.04 kg), lightly active. BMR = 10 × 68.039 + 6.25 × 165.1 − 5 × 30 − 161 = 1,401.26. Calories = 1,401.26 × 1.375 = 1,926.74. With 25 g of carbs (100 calories) and 35% protein (674.36 calories, 168.6 g), fat = (1,926.74 − 100 − 674.36) ÷ 9 = 128.0 g, a 59.8% share. Carbs are 5.2%: all inside the keto ranges.

A 35-year-old man, 5 ft 10 in, 180 lb, moderately active, losing 1 lb a week. BMR = 10 × 81.647 + 6.25 × 177.8 − 175 + 5 = 1,757.72; × 1.55 = 2,724.46; − 500 = 2,224.46 calories. 30 g carbs and 30% protein give 166.8 g of protein and 159.7 g of fat.

2,000 calories, 20 g carbs, 30% protein. Carbs 80 calories (4%); protein 600 calories (150 g); fat 1,320 calories (146.7 g, 66%). Fat is over 60% and carbs under 5%, so the check lists both.

Other questions people ask

How many carbs can I eat on keto?

A ketogenic diet usually keeps carbohydrate to 20 to 50 g a day, about 5% to 10% of the calories in a 2,000-calorie diet (StatPearls). The calculator starts at 25 g; set your own number.

What are the keto macro percentages?

StatPearls gives a typical split of about 55% to 60% of calories from fat, 30% to 35% from protein and 5% to 10% from carbohydrate. The calculator checks your split against these ranges.

How does the keto calculator work out my grams?

Carbs are the grams you type. Protein is your calories × the protein share ÷ 4. Fat is whatever calories are left, ÷ 9. At 2,000 calories with 20 g of carbs and 30% protein: carbs give 80 calories, protein 600 calories (150 g), and fat the other 1,320 calories (146.7 g).

How are my calories worked out?

From your basal metabolic rate (Mifflin-St Jeor, or the revised Harris-Benedict) times an activity factor from 1.2 to 1.9, less 250 calories a day for each 0.5 lb a week you want to lose.

Should I count total or net carbs?

The calculator counts the carbohydrate grams you type and does not subtract fibre. If you track net carbs (total carbohydrate less fibre), type that number, and keep in mind the 20 to 50 g range was given for carbohydrate.

Is a keto diet safe for everyone?

No. Talk to a doctor first, especially with diabetes medicines, kidney or liver disease, a history of eating disorders, or during pregnancy. The calculator is an estimate for planning, not medical advice.