CARB
CALCULATOR
Estimate your daily carbohydrate target from your calorie intake and goal, whether that's weight loss, maintenance, performance, or endurance training.
| Goal | Protein | Carbs | Fat | Notes |
|---|---|---|---|---|
| Fat Loss | 35% | 35% | 30% | High protein preserves muscle |
| Maintenance | 25% | 45% | 30% | Balanced approach |
| Muscle Gain | 25% | 50% | 25% | Extra carbs fuel training |
| Keto | 25% | 5% | 70% | Fat-fueled metabolic state |
| Endurance | 15% | 60% | 25% | Carbs for performance |
What This Calculator Does
The IndexBody Carb Calculator estimates how many grams of carbohydrate to eat each day based on your total daily calorie intake and your chosen goal. Enter your daily calorie target, pick a goal (weight loss, maintenance, performance, or endurance), and enter your body weight to see your carb target in grams, the calories those carbs provide, and a rough per-meal breakdown.
How the Calculation Works
Each goal is mapped to a percentage of daily calories allotted to carbohydrates: roughly 35% for weight loss, 45% for maintenance, 55% for performance, and 60% for endurance training. The calculator multiplies your daily calories by that percentage to get carb calories, then divides by 4 (since carbohydrate provides about 4 calories per gram) to get grams. This is a general starting point, not a personalized prescription — individual needs vary by body composition, training volume, and how your body responds to different carbohydrate intakes.
How Many Carbs Do You Need?
Carbohydrate needs vary based on activity level and goals. As a rough guide, sedentary adults often do well around 3–4g of carbohydrate per kg of body weight per day, while endurance athletes in heavy training may need closer to 6–10g/kg/day. Lower-carbohydrate approaches (under roughly 130g/day) can support weight loss for some people but may reduce capacity for high-intensity exercise. Many general dietary guidelines suggest roughly 45–65% of daily calories from carbohydrates for the average adult, though the right amount for you depends on your activity level, goals, and any medical conditions.
Why Carbohydrates Matter
Carbohydrates are the body's primary and most readily available fuel source, particularly for the brain and for higher-intensity exercise. Choosing mostly complex, minimally processed carbohydrates — whole grains, legumes, fruits, and vegetables — over refined sugars can support more stable energy levels and better overall nutrient intake. This calculator gives a starting estimate only; it does not diagnose, treat, or replace guidance from a registered dietitian or physician, especially if you have diabetes or another condition affected by carbohydrate intake.