Calculator inputs
Enter your body data, training demand, and goal. Results appear above this form after you calculate.
Example data table
| Scenario | Weight | Day type | Goal | Factor | Daily carbs |
|---|---|---|---|---|---|
| Desk worker with rest day | 70 kg | Rest | Fat loss | 2.0-2.5 g/kg | 140-175 g |
| General fitness session | 75 kg | Moderate | Maintenance | 5.0-5.8 g/kg | 375-435 g |
| Hypertrophy training block | 82 kg | Hard | Muscle gain | 6.5-7.5 g/kg | 533-615 g |
| Long endurance day | 68 kg | Endurance | Performance | 8.0-9.5 g/kg | 544-646 g |
| Two short sessions | 90 kg | Hard | Maintenance | 6.4-7.4 g/kg | 576-666 g |
Formula used
1) Unit conversion: Weight is converted to kilograms and height to centimeters before all core calculations.
2) BMR: Mifflin-St Jeor equation estimates resting calorie needs.
Male BMR = 10×kg + 6.25×cm − 5×age + 5
Female BMR = 10×kg + 6.25×cm − 5×age − 161
3) TDEE: TDEE = BMR × activity multiplier
4) Carb factor: The calculator starts with a day-type base factor, then adjusts it for goal, session intensity, duration, and extra sessions.
Carb factor = base + goal adj + intensity adj + duration adj + session adj
Daily carbs = carb factor × body weight in kg
5) Range: Lower and upper targets are built by subtracting or adding 0.75 g/kg around the main target.
6) Calories from carbs: Carb calories = daily carbs × 4
7) Timing split: Pre, intra, and post workout recommendations are drawn from the daily carb budget, then the remaining grams are divided across planned meals.
How to use this calculator
- Enter age, sex, body weight, height, and optional body fat.
- Choose your normal activity level to estimate overall energy output.
- Add today’s training minutes, number of sessions, and session intensity.
- Select your goal and the day type that best matches your workload.
- Enter how many meals you plan outside workout timing windows.
- Add a custom calorie target only if you already follow a set nutrition plan.
- Press calculate to show the result above the form.
- Review the chart, meal split, and rest day comparison.
- Use the CSV or PDF buttons to save or share the result.
Frequently asked questions
1) Is this calculator for athletes only?
No. It works for general fitness users, recreational lifters, fat-loss plans, and competitive athletes. Your inputs simply shift the carbohydrate factor upward or downward to match daily training stress.
2) Why does body weight drive the main estimate?
Sports nutrition guidance often uses grams per kilogram because muscle mass, training demand, and glycogen storage scale reasonably well with body size. It is a practical planning method.
3) Should I use the lower, middle, or upper range?
Use the middle number for most normal days. Use the lower end during lighter training or calorie deficits. Use the upper end for long sessions, double days, races, or heavy leg training.
4) Does the calculator replace a sports dietitian?
No. It is a structured planning tool. Medical conditions, gastrointestinal issues, diabetes, competition fueling, and making weight for sport may require tailored advice from a qualified professional.
5) What if I train fasted?
You can still use the daily target. Just move more carbohydrates into the meal after training or the evening before. Hard and long sessions generally benefit from more available carbohydrate.
6) Why does rest day intake look lower?
Rest days usually need less glycogen replacement. Lower carbs can still support recovery while making calorie control easier. Many people periodize intake by matching carbs to workload.
7) Should I count fiber in this target?
Yes, most food labels include fiber within total carbohydrate. For endurance fueling during sessions, many athletes prefer easily digested carb sources and may limit very high-fiber choices near training.
8) How often should I recalculate?
Recalculate when body weight, training volume, goal phase, or schedule changes. A new training block, event preparation, or diet phase can change carbohydrate needs meaningfully.