What is a Ketogenic Diet?
The ketogenic (keto) diet is a high-fat, low-carbohydrate eating plan that shifts your body into a metabolic state called ketosis. Instead of burning glucose from carbohydrates for energy, your body switches to burning fat and producing ketones — a highly efficient alternative fuel source.
Typical Keto Macros Ratio
- 70% Fats — the cornerstone of the keto diet: olive oil, avocado, nuts, butter, fatty fish, cheese
- 25% Protein — moderate protein to preserve muscle: eggs, meat, poultry, seafood
- 5% Carbohydrates — very low carbs to trigger ketosis: mostly non-starchy vegetables
Am I in Ketosis?
Your body typically enters ketosis within 2–4 days of limiting carbs to under 20–50 g per day. Signs of ketosis include:
- Reduced appetite and fewer cravings
- Increased mental clarity and focus
- A fruity or acetone-like breath (from ketone production)
- Initial fatigue or headaches (keto flu, usually temporary)
You can confirm ketosis using urine test strips, a blood ketone meter, or breath analyzers. Blood ketone levels of 0.5–3.0 mmol/L indicate nutritional ketosis.
How to Use This Free Keto Calculator
- Select your preferred unit system — Imperial (lbs, ft/in) or Metric (kg, cm)
- Enter your sex, age, weight, and height
- Choose your activity level (how much you move on a typical day)
- Select your goal — lose weight, maintain, or gain weight
- Leave the default 70/25/5 macro ratio or customize it for your needs
- Click Calculate to get your personalized keto macros
What is the Recommended Keto Macros Ratio?
The standard keto macros ratio is 70% fat / 25% protein / 5% carbohydrates. Some variations exist:
- Standard Keto (SKD): 70% fat / 25% protein / 5% carbs — the most common approach
- High-Protein Keto: 60% fat / 35% protein / 5% carbs — popular with athletes
- Cyclical Keto (CKD): 5–6 keto days followed by 1–2 higher-carb days
- Targeted Keto (TKD): standard keto with extra carbs around workouts
What Foods Should I Eat on a Keto Diet?
- Healthy fats: avocado, olive oil, coconut oil, butter, ghee, MCT oil
- Proteins: beef, chicken, turkey, pork, eggs, salmon, tuna, sardines
- Low-carb vegetables: spinach, kale, broccoli, cauliflower, zucchini, peppers
- Dairy: cheese, heavy cream, full-fat Greek yogurt (in moderation)
- Nuts & seeds: almonds, walnuts, macadamias, chia seeds, flaxseed
Foods to Avoid on the Ketogenic Diet
- Grains & starches: bread, pasta, rice, cereal, oatmeal
- Sugar & sweets: candy, cake, cookies, ice cream, soda, juice
- Most fruits: bananas, apples, oranges, grapes (berries in small amounts are OK)
- Legumes: beans, lentils, chickpeas, peas
- Root vegetables: potatoes, sweet potatoes, carrots, parsnips
- Alcohol: beer, sweet wine, cocktails (dry wine and spirits in moderation)
What is Keto Flu?
Keto flu is a collection of symptoms that some people experience during the first 1–2 weeks of the keto diet as the body adapts to burning fat instead of carbohydrates. Common symptoms include headache, fatigue, brain fog, nausea, irritability, and difficulty sleeping.
To minimize keto flu:
- Stay well hydrated — drink plenty of water
- Replenish electrolytes (sodium, potassium, magnesium)
- Ease into the diet gradually rather than cutting carbs abruptly
- Get enough sleep and rest
Health Benefits of the Keto Diet
- Weight loss: ketosis accelerates fat burning, often producing faster results than low-fat diets
- Blood sugar control: significantly reduces blood glucose and insulin levels
- Reduced hunger: high fat intake promotes satiety and reduces appetite
- Improved mental clarity: many users report enhanced focus and concentration
- Epilepsy management: clinically proven to reduce seizures, especially in children
- Triglyceride reduction: low-carb diets typically lower blood triglyceride levels
Frequently Asked Questions
How many carbs can I eat on keto?
Most people need to stay below 20–50 g of net carbs per day to maintain ketosis. Net carbs = total carbs minus dietary fiber. Beginners should aim for 20 g to reliably enter ketosis.
How much protein is too much on keto?
Excess protein can be converted to glucose through gluconeogenesis, potentially kicking you out of ketosis. As a rule of thumb, aim for 0.6–1.0 g of protein per pound (1.3–2.2 g/kg) of lean body mass per day.
Can I drink coffee on keto?
Yes — black coffee, espresso, and Americano are fine. Many keto dieters add butter or MCT oil (bulletproof coffee) for an extra fat boost. Avoid sugar and high-carb creamers.
Is keto safe long-term?
Research on long-term keto is still evolving. Short-term studies show strong benefits for weight loss and metabolic health. Always consult a healthcare professional before starting any restrictive diet, especially if you have diabetes, kidney disease, or other chronic conditions.