THE NUMORIX GUIDE
How to use the Carb Intake Calculator
Last reviewed September 14, 2026
What this calculator does
The engine assigns a base carbohydrate factor in grams per kilogram: 3 sedentary, 4 light, 5 moderate, 7 intense, or 10 athlete.
Formula and method
The engine assigns a base carbohydrate factor in grams per kilogram: 3 sedentary, 4 light, 5 moderate, 7 intense, or 10 athlete. It subtracts 1 for the lose goal or adds 2 for gain, then calculates daily carbs = weight * adjusted factor, carbohydrate calories = grams * 4, and percentage = carbohydrate calories / (weight * 30) * 100.
Variables and inputs
Weight is in kilograms, activity is one of five labels, and the goal is maintain, lose, or gain. The route does not ask for actual calorie needs; its percentage denominator is a fixed estimate of 30 kcal per kilogram of body weight.
Worked example
For 70 kg, moderate activity, and maintain: the factor is 5, so daily carbs = 70 * 5 = 350 g; calories from carbs = 350 * 4 = 1,400 kcal; the displayed percentage is 1,400 / (70 * 30) * 100 = 66.7%.
How to interpret the result
The gram result is a heuristic based on body weight, activity label, and goal adjustment. The percentage is not the share of the person's actual daily calories unless 30 kcal/kg happens to match those calories.
Common mistakes to avoid
Do not treat the percentage as a measured macro split, and do not confuse total carbohydrate with net carbohydrate or fiber. Enter kilograms and select the activity that reflects regular training, not a single hard session.
Assumptions and limitations
Factors are hardcoded and do not account for diabetes treatment, pregnancy, kidney disease, age, sport duration, total energy needs, medication, or carbohydrate tolerance. The engine does not validate weight or use a calorie input, so its target may be unsuitable for an individual diet.