Keto calculator
On keto, carbs are limited to 5–10% of calories — roughly 20–50 g a day — and most energy comes from fat. The calculator works out your calorie needs and splits them into carbs, protein and fat in keto proportions.
Calories are calculated with the Mifflin–St Jeor equation, as in the calorie calculator. Keto does not change the arithmetic: weight comes off through a calorie deficit, on keto as on any other diet.
The split is the typical keto ratio from the StatPearls review: 55–60% of calories from fat, 30–35% from protein, 5–10% from carbs. For weight loss, keto usually works as a very low-carb diet: 20–50 g of carbs a day without a strict ratio.
How it works
- Enter your sex, age, weight, height and activity, and choose your goal.
- Look at the carb range: that is the core limit of keto and the one to keep to.
- Make up the rest of your calories with protein and fat. Weigh and log your food for the first few weeks: carbs from vegetables, nuts and dairy are easy to underestimate.
Who should not do keto
During pregnancy and breastfeeding, and with pancreatic, liver or kidney disease, keto is not something to start without a doctor. With diabetes, especially on insulin or SGLT2 inhibitors (gliflozins), switching to keto without medical supervision is dangerous: cutting carbs sharply while on these drugs raises the risk of ketoacidosis.
The only condition for which keto appears in clinical guidelines is drug-resistant epilepsy. Compared with low-fat diets, the difference in weight lost after a year is about one and a half kilograms, which is closer to parity than to an advantage. More in Keto diet: what happens in the body.
| Calories | Keto split per day |
|---|---|
| 1,500 kcal | carbs 19–38 g, protein 113–131 g, fat 92–100 g |
| 1,800 kcal | carbs 23–45 g, protein 135–158 g, fat 110–120 g |
| 2,000 kcal | carbs 25–50 g, protein 150–175 g, fat 122–133 g |
| 2,400 kcal | carbs 30–60 g, protein 180–210 g, fat 147–160 g |
Frequently asked questions
- How many carbs can I eat on keto?
- Usually 20–50 g a day, or 5–10% of calories. That covers all carbs: vegetables, berries, dairy, nuts and sauces.
- How much protein do I need on keto?
- In the typical split from the StatPearls review, 30–35% of calories. When losing weight, protein helps preserve muscle.
- Do I need to count calories on keto?
- Yes, if your goal is weight loss. Weight comes off through a calorie deficit, not through ketosis itself.
Further reading
- Keto diet: what happens in the body and what comparisons have shown
- How many carbs do you need per day?
- Macro ratio: where the percentages come from
More calculators: Caffeine calculator, Recipe calorie calculator, Exercise calorie calculator, Post-workout protein calculator.
This calculator gives an estimate for general information. It is not medical advice, a diagnosis, or a prescription for treatment or a diet, and it does not replace a consultation with your doctor. If you have a health condition, are pregnant, take medication, or follow a diet prescribed to you, decisions about food belong with your doctor.