π₯ Keto Macro Calculator
Ketogenic targets: low carb, right protein, fat to satiety.
For informational purposes only, not medical advice. Consult a healthcare professional.
Keto macros follow a strict order of operations: net carbs get a hard cap, protein gets a fixed target to protect muscle, and fat fills whatever calories remain. Net carbs are total carbs minus fiber (and half of sugar alcohols), because fiber does not raise blood sugar. Most people enter nutritional ketosis staying under 50 grams of net carbs daily; 20 to 30 is the standard starting cap.
This calculator sets your calories from the Mifflin-St Jeor equation and your goal, caps net carbs at your chosen level, fixes protein at 0.8 grams per pound, and assigns the rest to fat. Fat is the flexible macro on keto: eat to satiety within the calorie target rather than force-feeding fat.
How to Use This Calculator
Enter your stats and activity level, pick lose or maintain, and choose a net carb cap: 20 strict, 30 standard, 50 liberal. Hit the protein target daily, stay under the carb cap, and let fat land where appetite takes it inside the calorie budget. Track net carbs, not total carbs, by subtracting fiber.
Enter stats, activity, and goal.
Pick your net carb cap: 20, 30, or 50 grams.
Hit the protein grams daily; it protects muscle while carbs stay low.
Keep net carbs under the cap and let fat fill the remaining calories to satiety.
The Keto Priority Order
Protein = 0.8 x weight (lb)
Fat (g) = (calories - protein x 4 - net carbs x 4) / 9
Carbs are capped first because ketosis is a carb threshold phenomenon: liver glycogen depletes within a day or two under 50 grams, and the liver starts making ketones. Protein is set at 0.8 g per pound because the old keto fear that protein "kicks you out of ketosis" via gluconeogenesis is overstated; gluconeogenesis is demand-driven, not supply-driven, and skimping protein costs muscle. Fat fills the remainder because it is the only macro left, and dietary fat has minimal insulin impact. The calorie target still governs fat loss: keto works through appetite suppression and adherence, not a metabolic exemption from energy balance.
Worked Example
A 32-year-old man, 175 cm, 90 kg, sedentary and cutting: 1,765 cal per day with 30 g (hard cap), 159 g (0.8 g/lb), and 112 g (fills remaining calories). Fat supplies ~1,010 cal (57%) of the day, the classic keto split near 70-75% fat calories. Raise the carb cap to 50 g and fat drops by about 5 grams to keep calories constant.
Reading Your Keto Targets
The net carb cap is a ceiling, not a goal: coming in under it is the whole point. Protein is the daily must-hit; low protein on keto is the fastest route to losing muscle along with fat. Fat is a lever: eat less of it than the target and you deepen the deficit, eat to the target for maintenance. If ketosis stalls, the usual culprits are hidden carbs (sauces, drinks, "keto" snacks), not the protein number. Electrolytes deserve attention in week one: sodium, potassium, and magnesium needs rise as insulin drops and the kidneys excrete more water.
| Macro | Role | Rule |
|---|---|---|
| Net carbs | Ketosis gatekeeper | Stay under the cap |
| Protein | Muscle protection | Hit 0.8 g/lb daily |
| Fat | Energy + satiety | Fill remaining calories |
| Fiber | Digestion | 25-35 g from low-carb veg |
Keto Is Not for Everyone
Talk to your doctor first if you take diabetes medications (especially insulin or sulfonylureas), have kidney disease, are pregnant, or have a history of eating disorders: keto changes medication needs and is contraindicated in some conditions. Very high triglycerides, pancreatitis history, and fat-malabsorption disorders also need medical input. For informational purposes only, not medical advice. Consult a healthcare professional.
Related tools: net carbs calculator, IIFYM macro calculator and TDEE calorie calculator.
For informational purposes only, not medical advice. Consult a healthcare professional.
Frequently Asked Questions
How many net carbs keep you in ketosis?
Most people stay in ketosis under 50 g of net carbs daily; 20 to 30 g is the standard starting cap. Athletes and very active people sometimes tolerate more.
What are net carbs?
Total carbohydrates minus fiber, minus about half of sugar alcohols. Fiber does not raise blood sugar, so it does not count against the carb cap.
Will too much protein kick me out of ketosis?
Probably not. Gluconeogenesis is demand-driven, and studies show higher protein intakes do not meaningfully reduce ketone levels. Skimping protein costs muscle instead.
Why do I feel awful in week one?
The "keto flu": as insulin drops, kidneys excrete sodium and water, taking potassium and magnesium along. Broth, salt, and electrolytes fix most of it within days.
How much fat should I eat on keto?
Enough to feel satisfied within your calorie target. Fat is a lever: less fat deepens a deficit, more fat holds maintenance.
How do I know I am in ketosis?
Blood ketone meters (0.5 mmol/L and up indicates nutritional ketosis) are the reliable check. Urine strips work early on but become unreliable as the body adapts.
Can I do keto as a vegetarian?
Yes with planning: eggs, dairy, tofu, tempeh, nuts, and low-carb vegetables. It is harder than omnivore keto but workable.
Is keto safe long term?
Studies show benefits for weight and metabolic markers at 1 to 2 years with medical supervision. Long-term data is thinner; periodic labs and a clinician in the loop are wise.