Keto Macro Calculator: Fat, Protein & Net Carbs
Set your carb limit and goal; get grams of fat, protein and net carbs for the day.
Keto macros for weight loss
A standard ketogenic split is about 70–75% of calories from fat, 20–25% from protein and 5–10% from carbohydrate, usually 20–50 g net carbs a day. Weight loss on keto still requires a calorie deficit; the calculator starts from your TDEE, subtracts the deficit you choose, fixes protein and carbs, and gives the remainder to fat.
Net carbs explained
Net carbs = total carbohydrate − fibre (and, on labels, − sugar alcohols). Fibre is not digested into glucose, so it does not count against the carb limit. Our Nutrition Facts pages list both totals; the nutrition label guide shows where to find them.
Keto macros for women
The percentages are the same; the grams are lower because calorie needs are lower. A 65 kg woman on 1,500 calories at 25 g net carbs might land at about 115 g fat, 95 g protein, 25 g carbs. Protein at 1.2–1.7 g/kg protects muscle; going too low on protein to “stay in ketosis” is a common mistake.
How the keto calculator works
1) Estimate TDEE with Mifflin-St Jeor. 2) Apply your goal (deficit, maintenance or surplus). 3) Set net carbs (default 25 g) and protein by body weight. 4) Fill the remaining calories with fat at 9 kcal/g. Change the carb limit or protein ratio and everything recalculates.
Sources
- Dietary Guidelines for Americans (current edition; AMDR) — https://www.dietaryguidelines.gov/
- Mifflin-St Jeor equation, PubMed 2305711 — https://pubmed.ncbi.nlm.nih.gov/2305711/
- Harvard T.H. Chan Nutrition Source, Diet review: ketogenic diet — https://nutritionsource.hsph.harvard.edu/healthy-weight/diet-reviews/ketogenic-diet/
This calculator is educational and not medical advice. If you have a health condition, are pregnant, or are under 18, ask a clinician before changing your diet.
What the result tells you
A ketogenic split of your calories — high fat, moderate protein, very low carbohydrate — at a slight deficit.
How to use it
- Set protein first, keep net carbs under the target, then fill the rest with fat.
- Track net carbs (total carbs minus fibre), not total carbs.
- Expect 2–4 weeks to fully adapt before judging how you feel.
Recommendations
- Prioritise whole-food fats and protein over processed 'keto' products.
- Salt, magnesium, and potassium help with early-adaptation fatigue.
- Keto isn't required to lose fat — it's one approach among several.
Health & wellbeing
Very low-carb eating isn't right for everyone — including some people with certain medical conditions or on specific medications. Check with a professional first.
Troubleshooting
Numbers feel extreme? Keto deliberately front-loads fat. If it doesn't suit you, a balanced split works just as well for fat loss.
How it’s calculated
Calories are set slightly below maintenance, then divided into the standard ketogenic ratio.
Calories = TDEE × 0.95. Fat = 70% ÷ 9 · Protein = 25% ÷ 4 · Net carbs = 5% ÷ 4.
Source: TDEE via Mifflin–St Jeor (1990); ketogenic ratio per common clinical practice.
Common questions
How many carbs keep you in ketosis?
Most people stay in nutritional ketosis under about 50 g net carbs a day; some need under 20 g.
Is keto safe long term?
Evidence beyond 1–2 years is limited; people with kidney, liver or pancreatic conditions, or on diabetes medication, should not start without medical supervision.
Do I need to eat all the fat?
Fat is the flexible macro: if you are not hungry, eat less and the deficit grows.