🥑Keto Calculator
Calculate your personalised keto macros — fat, protein, and net carbohydrates — based on height, weight, age, sex, activity level, and goal. Supports Standard (SKD), Strict, High-Protein, and Targeted ketogenic diet plans.
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Target Daily Calories (kcal)
1,905
Keto Macro Distribution (calories)
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Keto Calculator: How to Calculate Your Keto Macros Correctly
The standard ketogenic diet (SKD) allocates roughly 70% of calories from fat, 25% from protein, and 5% from carbohydrates, with a net carb ceiling of 50g per day. At these low carbohydrate levels, liver glycogen is depleted within 1–3 days and the liver begins producing ketone bodies (β-hydroxybutyrate, acetoacetate, acetone) from fatty acids — a metabolic state called nutritional ketosis.
Formula: Fat (g) = Target Calories × 0.70 ÷ 9 | Protein (g) = Target Calories × 0.25 ÷ 4 | Net Carbs = Total Carbs − Fiber
| Keto Type | Fat / Protein / Carbs | Max Net Carbs |
|---|---|---|
| Standard (SKD) | 70% / 25% / 5% | 50g |
| Strict / Classic | 75% / 20% / 5% | 20g |
| High-Protein (HPKD) | 60% / 35% / 5% | 50g |
Our keto calculator uses the Mifflin-St Jeor equation to calculate your Basal Metabolic Rate (BMR), then multiplies by an activity factor to get your Total Daily Energy Expenditure (TDEE). A deficit or surplus is applied based on your goal, and the resulting calorie target is split according to your chosen keto variant. The output shows gram targets for fat, protein, total carbs, and net carbs — the values that matter most for maintaining ketosis.
What Are Net Carbs and Why Do They Matter on Keto?
Net carbs represent the carbohydrate grams that actually affect blood glucose and insulin levels. The formula is: Net Carbs = Total Carbohydrates − Fibre. Fibre passes through the digestive tract without being absorbed as glucose, so it does not trigger an insulin response and does not disrupt ketosis. Some low-carb advocates also subtract sugar alcohols (like erythritol, which has essentially zero glycaemic impact), though others subtract only 50% of sugar alcohol grams given variable individual responses.
For most people, staying below 20–50g of net carbs per day is sufficient to enter and maintain ketosis. The precise threshold varies individually — some people maintain ketosis at 60–70g net carbs (particularly those with high activity levels), while others with insulin resistance may require under 20g. Blood ketone measurement (β-hydroxybutyrate above 0.5 mmol/L) is the definitive test for nutritional ketosis.
Protein on Keto: Getting the Amount Right
Protein intake is one of the most misunderstood aspects of ketogenic dieting. Too little protein causes muscle loss, especially during calorie deficits; too much protein can theoretically inhibit ketosis through gluconeogenesis (conversion of amino acids to glucose). In practice, the gluconeogenic effect of dietary protein is demand-driven, not supply-driven — excess protein amino acids are not automatically converted to glucose in most people.
Current evidence suggests that protein intake of 1.6–2.2g per kg of body weight per day is optimal for preserving lean mass during fat loss. Standard SKD at 25% protein typically delivers 1.6–2.0g/kg for most adults at a normal calorie deficit, which is appropriate. High-protein keto (HPKD) at 35% protein provides extra margin for athletes and older adults with higher protein needs for muscle protein synthesis. A practical target: 30–35% of calories from protein is safe and beneficial for the vast majority of keto dieters.
The Keto Flu: What It Is and How to Prevent It
The "keto flu" — symptoms including fatigue, headache, brain fog, nausea, muscle cramps, and irritability — affects an estimated 25–45% of people in the first 1–2 weeks of a ketogenic diet. The primary mechanism is electrolyte loss: as insulin levels fall and glycogen is depleted, the kidneys reduce sodium reabsorption and excrete substantially more sodium, potassium, and magnesium. The resulting electrolyte depletion is responsible for most keto flu symptoms.
Prevention strategy: increase sodium to 3,000–5,000mg/day (salt food generously, use salted broths), potassium to 3,500–4,700mg/day (from avocados, leafy greens, salmon), and magnesium to 300–500mg/day (supplements or dark leafy greens). Adequate hydration (3–4L/day) is also essential. Most people who supplement electrolytes proactively report minimal keto flu symptoms.
Frequently Asked Questions
How many carbs can you eat on keto?
Standard ketogenic diets limit net carbs to 20–50g per day. Most people enter ketosis below 50g net carbs; strict protocols cap at 20g for faster or more reliable ketosis induction. "Net carbs" means total carbohydrates minus dietary fibre (and optionally minus certain sugar alcohols). Total carbohydrate intake is typically 5% of calories — approximately 20–30g at a 1,500–2,000 kcal intake. Individual carb tolerance varies; blood ketone testing confirms whether you're in ketosis at your current carb level.
How long does it take to enter ketosis?
Most people enter measurable nutritional ketosis (β-hydroxybutyrate ≥0.5 mmol/L) within 2–4 days of strict carb restriction below 20–50g net carbs per day. The timeline depends on glycogen stores at the start: more active individuals with lower glycogen deplete it faster. Full "keto adaptation" — where the body and brain become efficient at using ketones rather than glucose — takes 3–6 weeks. Exercising in a fasted state, doing moderate cardio, or short-term fasting can accelerate initial ketosis induction.
Is keto safe long-term?
Well-formulated ketogenic diets that include diverse non-starchy vegetables, adequate protein, and healthy fat sources are generally safe for most healthy adults for extended periods. Clinical evidence supports keto for management of drug-resistant epilepsy (decades of data), type 2 diabetes remission, and metabolic syndrome. Potential concerns with very long-term use include: changes in LDL particle count (variable — may increase in some), reduced fibre intake and altered gut microbiome diversity, and kidney stone risk (especially with the classic 4:1 ratio therapeutic diet). People with certain conditions (pancreatitis, liver failure, disorders of fat metabolism) should not use keto without medical supervision.
What is the difference between Standard Keto and Strict Keto?
Standard Keto (SKD) allocates 70% fat, 25% protein, 5% carbs with a net carb limit of 50g/day — suitable for most general health, weight loss, and performance goals. Strict/Classic Keto (75% fat, 20% protein, 5% carbs, ≤20g net carbs/day) was originally developed for epilepsy management and produces higher, more consistent blood ketone levels. The strict version is appropriate for therapeutic uses or for people who find they cannot achieve consistent ketosis at the standard 50g net carb ceiling. Both are valid approaches; the strict version requires more careful planning to get adequate nutrition.
Do I need to count calories on keto?
In theory, the appetite-suppressing effect of ketones and high fat/protein intake makes calorie tracking less necessary than on other diets. However, weight loss ultimately follows an energy deficit, and keto does not override thermodynamics. Many people naturally eat less on keto due to reduced appetite. For intentional fat loss — especially if results have plateaued — tracking calories and macros (fat, protein, net carbs) is the most reliable approach. For general health maintenance, most people on a well-formulated keto diet eat to satiety without counting.