Keto Calculator

The ketogenic (keto) diet is a very low-carb, high-fat diet that shifts your body into a metabolic state called "ketosis." Normally, your body runs on glucose (sugar) from carbs as its primary fuel. But when you drastically reduce carbs to 20-50g net carbs per day and increase fat intake to 60-75% of calories, your body runs out of glucose and starts breaking down fat into molecules called "ketones" for energy instead. This usually happens within 2-4 days of strict carb restriction. In ketosis, your liver converts fat (both dietary fat and body fat) into ketones, which your brain and body use as fuel. This metabolic switch has several effects: reduced insulin levels (which stops fat storage), increased fat burning, reduced appetite (ketones suppress hunger hormones), and steady energy levels without the blood sugar crashes you get from carbs.

For most people, staying in ketosis requires 20-50g of NET carbs daily (net carbs = total carbs minus fiber). Here's the breakdown: Standard Keto (SKD) is the strictest at 20-25g net carbs - best for rapid fat loss and getting into ketosis quickly. Targeted Keto (TKD) allows 30-50g net carbs, with the extra carbs consumed around workouts for athletic performance. Cyclical Keto (CKD) alternates 5 strict keto days with 2 higher-carb days (150-200g). Most beginners should start with Standard Keto at 20g net carbs to guarantee ketosis. Some very active people can stay in ketosis up to 50g, but that's rare. The key is NET carbs - you subtract fiber because your body doesn't digest it, so it won't kick you out of ketosis. For example, 10g total carbs with 5g fiber = 5g net carbs.

Keto is all about high-fat, moderate-protein, very low-carb foods. Your best friends: Healthy fats (70% of plate): avocados, olive oil, coconut oil, butter, ghee, MCT oil, fatty fish (salmon, mackerel), nuts and seeds (macadamia, pecans, almonds), cheese, heavy cream. Protein (25% of plate): beef, pork, chicken, turkey, eggs, bacon, fatty fish, shellfish - aim for fattier cuts! Low-carb veggies (5% of plate): leafy greens (spinach, kale, lettuce), cruciferous veggies (broccoli, cauliflower, Brussels sprouts), zucchini, asparagus, mushrooms, bell peppers. Limit to 1-2 servings daily since they have some carbs. Drinks: water, coffee, tea, bone broth, diet sodas (occasionally). The key is flipping the food pyramid upside down - fat becomes your main fuel source, not carbs!

Anything high in carbs will kick you out of ketosis fast! Absolute NO-GO foods: All grains (bread, pasta, rice, cereal, oats - even "healthy" whole grains), all sugar (candy, cookies, cakes, ice cream, honey, maple syrup), all starchy vegetables (potatoes, sweet potatoes, corn, peas), most fruits (bananas, apples, oranges, grapes - too much sugar), all legumes (beans, lentils, chickpeas - surprisingly high carb), milk (too much lactose sugar), low-fat products (they add sugar to replace fat), most sauces and condiments (ketchup, BBQ sauce, teriyaki - loaded with hidden sugar), beer and sweet alcohols (pure sugar bombs). Be especially careful with "keto" products and packaged foods - many have hidden carbs and maltitol (a sugar alcohol that DOES affect blood sugar despite marketing claims). Read labels obsessively!

The "keto flu" isn't actually the flu - it's your body throwing a tantrum during the first 3-7 days as it switches from burning glucose to burning fat. Symptoms include headaches, fatigue, brain fog, irritability, nausea, dizziness, muscle cramps, and insomnia. Sounds awful, right? Here's why it happens: when you cut carbs, your insulin drops, making your kidneys dump lots of water and electrolytes (especially sodium, potassium, and magnesium). You're literally dehydrated and depleted! The fix is simple: 1) Drink 3-4 liters of water daily, 2) Add 5,000mg of sodium (2 teaspoons of salt throughout the day - put it in water, on food, everywhere!), 3) Get 1,000mg potassium (avocados, spinach, or No-Salt supplement), 4) Take 300-400mg magnesium before bed, 5) Don't cut calories too low - eat to satiety with fat. Do this and you can completely avoid or minimize keto flu!

Most people enter ketosis within 2-4 days of staying under 20g net carbs, but it varies based on several factors. If you're coming from a high-carb diet (200-300g daily), your liver has lots of stored glycogen (stored carbs) to burn through first - this takes 2-3 days. If you're already eating moderate carbs (50-100g), you might enter ketosis in 24-48 hours. Athletes with depleted glycogen from intense workouts can enter ketosis in 12-24 hours! Ways to speed it up: 1) Exercise intensely to burn glycogen stores faster, 2) Fast for 16-24 hours (intermittent fasting), 3) Add MCT oil (converts directly to ketones), 4) Keep carbs at 20g or below (not 30-40g). You'll know you're in ketosis when: breath smells fruity/metallic, increased urination, reduced appetite, steady energy, and ketone meter shows 0.5-3.0 mmol/L.

Yes, but it's more challenging than on a higher-carb diet! Carbs help with muscle building by spiking insulin (anabolic hormone), filling glycogen stores for intense workouts, and providing quick energy. Without carbs, you need to optimize everything else: 1) Eat ENOUGH protein - 1.0-1.2g per pound of body weight (higher than standard keto), 2) Eat at a calorie surplus of 200-300 calories above TDEE, 3) Time protein around workouts (30-40g within 2 hours post-workout), 4) Consider Targeted Keto (TKD) - eat 25-30g fast-digesting carbs 30 minutes before workouts for glycogen, 5) Do progressive overload strength training 4-5x per week, 6) Be patient - muscle gains on keto are 15-20% slower than high-carb but you'll stay leaner. Many bodybuilders use Cyclical Keto (CKD) - 5 keto days, 2 carb-refeed days for best of both worlds.

Weight loss on keto varies wildly! Week 1: Most people lose 5-10 pounds (mostly water weight from glycogen depletion - each gram of glycogen holds 3g of water). Don't get too excited, this isn't all fat! Weeks 2-4: Fat loss kicks in at 1-3 pounds per week depending on your calorie deficit, starting weight, and metabolism. Month 2-3: Fat loss slows to 1-2 pounds per week as your body adapts. Long-term: Expect 0.5-2 pounds per week sustainably. A 500-calorie daily deficit = 1 pound per week fat loss. Real-world examples: Someone with 100+ pounds to lose might drop 15-20 pounds the first month, then 8-10 pounds monthly after. Someone with 20 pounds to lose might drop 5-7 pounds first month, then 3-4 pounds monthly. The key factors: calorie deficit (keto isn't magic if you overeat!), protein intake (preserve muscle), consistency (cheating resets progress), and starting weight (more to lose = faster initial loss).

The research shows keto is safe for most people for 1-2 years, but long-term data (5+ years) is limited. Potential benefits: sustained fat loss, improved insulin sensitivity and blood sugar control (great for pre-diabetics), higher HDL (good cholesterol), reduced triglycerides, mental clarity, reduced inflammation. Potential concerns: Nutrient deficiencies if not eating enough variety (fiber, vitamins C/D, magnesium, potassium), kidney stones (rare, but possible from high protein + dehydration), digestive issues from lack of fiber, higher LDL cholesterol in some people (though particle size usually improves), social challenges (hard to eat out or with family). Who should avoid keto: pregnant/breastfeeding women, people with kidney disease, people with eating disorder history, type 1 diabetics (risk of ketoacidosis). The verdict? Keto appears safe for 1-2 years for most healthy adults, but consider "cycling" - do keto for 3-6 months, then transition to low-carb (50-100g) for maintenance.

All keto diets are low-carb, but not all low-carb diets are keto! The key difference is KETOSIS. Keto diet: 20-50g net carbs daily, specifically designed to put you in nutritional ketosis (0.5-3.0 mmol/L blood ketones), your body runs primarily on ketones/fat for fuel, requires strict macro tracking, therapeutic benefits beyond weight loss. Low-carb diet: 50-150g carbs daily, you're NOT in ketosis, your body still runs on glucose but less of it, more flexible and sustainable for many people, still effective for weight loss. Think of it like a spectrum: High-carb (200-300g) → Moderate-carb (100-200g) → Low-carb (50-100g) → Keto (20-50g) → Carnivore (0-5g). Many people find long-term success by doing strict keto for 2-3 months to lose weight, then transitioning to low-carb (75-100g) for maintenance. This gives the weight loss benefits of ketosis without the long-term restriction challenges.