Daily Carb Grams: The total grams of carbohydrates you would eat per day at your chosen ratio. One gram of carbohydrate provides 4 calories, so this is derived directly from your calorie target and percentage.
Carb Calories: The portion of your daily calories supplied by carbohydrates. The remaining calories are available for protein and fat.
Remaining Calories: What is left after carb calories are subtracted. You would typically split this between protein (4 cal/g) and fat (9 cal/g) based on your goals.
Carbs Per Meal: A rough per-meal target assuming three meals per day. If you eat more or fewer meals, divide your daily grams accordingly.
How This Calculator Works
You enter your total daily calorie target and pick a carb ratio — low (20%), moderate (45%), high (60%), or a custom percentage. The tool multiplies calories by that ratio to get carb calories, then divides by 4 to convert to grams. It also shows the leftover calories for protein and fat, and splits carb grams across three meals. Actual needs depend on activity level, goals, and medical context.
Quick Questions
What percentage of carbs is considered low-carb?
Most nutrition guidelines consider anything under 26% of total calories as low-carb. Very low-carb or ketogenic diets typically aim for 5–10%. The 20% preset here represents a moderate low-carb approach.
Why does each gram of carbs equal 4 calories?
This is a standard biochemistry value known as the Atwater factor. Carbohydrates and protein each provide about 4 calories per gram, while fat provides about 9 calories per gram. These values are used universally in nutrition labeling.
Should I adjust my carb ratio for exercise?
Generally, more active individuals benefit from a higher carb percentage to fuel workouts and recovery. Endurance athletes may go as high as 60–70%, while sedentary individuals may do well at 40–50%. Consult a dietitian for personalized guidance.
Does this calculator account for fiber?
No. The calculator treats all carbohydrates equally. In practice, fiber is a carbohydrate that is not fully digested, so some people subtract fiber grams to get "net carbs." This distinction matters most for ketogenic diets.