The ketogenic diet shifts your body’s primary fuel source from glucose (carbohydrates) to ketones (from fat). But getting into and staying in ketosis requires specific macro ratios that vary by individual body composition, activity level, and goal. Our keto macros calculator generates personalized targets — here is how to understand and use them.
How Ketosis Works
When carbohydrate intake drops below approximately 20-50g net carbs per day, glycogen stores deplete over 2-4 days, and the liver begins converting fatty acids to ketone bodies as an alternative fuel. This metabolic state — nutritional ketosis — is what the keto diet aims to achieve and maintain.
The Standard Keto Macro Breakdown
| Macro | Percentage | Why |
|---|---|---|
| Fat | 70-75% | Primary fuel source in ketosis |
| Protein | 20-25% | Preserves muscle; too much converts to glucose |
| Net Carbs | 5% (max 20-25g) | Keep carbs below ketosis threshold |
Net Carbs vs Total Carbs
Net carbs = Total carbs − Fiber − Sugar alcohols. Fiber passes through undigested and doesn’t raise blood sugar or affect ketosis. Sugar alcohols (erythritol has minimal impact; maltitol raises blood sugar significantly). Only net carbs count toward your keto limit.
What to Eat and Avoid
Eat Freely
Meat, fish, seafood, eggs, full-fat dairy (cheese, cream, butter), oils (olive, avocado, coconut), most vegetables above ground (leafy greens, broccoli, cauliflower, zucchini).
Avoid Completely
Bread, pasta, rice, most fruit (berries in small amounts are OK), sugar and sweeteners that raise blood sugar, legumes, root vegetables (potatoes, sweet potatoes), most packaged snacks.
Common Keto Mistakes
- Too much protein — excess protein can be converted to glucose (gluconeogenesis) and potentially kick you out of ketosis
- Not enough sodium — keto reduces insulin, causing kidneys to excrete more sodium. Add salt to food and consider electrolytes
- Ignoring calories — keto doesn’t suspend calories-in/calories-out. You still need a deficit to lose weight
- Cheat days — one high-carb day resets ketosis, requiring 2-4 days to re-enter
Keto Meal Planner and Macro Tracker
Weekly keto meal planning template with built-in macro tracking for each meal. Stay on target with daily and weekly summaries.
Get the Keto Planner →Typically 2-4 days of strict low-carb eating (under 20g net carbs). Combining low carbs with exercise (which depletes glycogen faster) can achieve ketosis in 1-2 days. Signs of ketosis: reduced hunger, increased urination, “keto breath” (acetone on breath), mental clarity after initial adaptation.
Research shows ketogenic diets are generally safe for healthy adults for 1-2 years. Long-term studies beyond 2 years are limited. People with diabetes, kidney disease, or certain metabolic conditions should consult a doctor before starting keto. The primary concern is nutrient deficiency if food variety is too restricted.