Protein Calculator
Estimate your daily protein target from body weight and goal, with a target range, protein calories, and per-meal protein guidance.
Results
This calculator provides a general nutrition estimate only. Protein needs can vary by age, training level, medical conditions, pregnancy, kidney health, total calories, and body composition goals. For clinical or medical nutrition advice, consult a qualified professional.
Use this Protein Calculator to estimate a daily protein target from body weight and a selected grams-per-kilogram goal. It can also estimate protein calories, protein per meal, and the percentage of daily calories supplied by protein.
Important: Protein needs vary with age, activity, training, total calorie intake, pregnancy, health conditions, and individual goals. This calculator provides a general nutrition estimate rather than a medical diet prescription.
Protein Calculation Formula
If weight is entered in pounds:
Weight in kg = weight in lb ÷ 2.20462
The main calculation is:
Daily protein = body weight in kg × selected protein target in g/kg/day
Protein provides approximately 4 kcal per gram:
Protein calories = daily protein grams × 4
If you select a number of meals:
Protein per meal = daily protein ÷ meals per day
If daily calories are entered:
Protein share of calories = protein calories ÷ daily calories × 100
Choosing a Protein Target
For generally healthy adults, the longstanding Recommended Dietary Allowance is approximately 0.8 g/kg/day. People who exercise regularly may use higher targets; sports-nutrition guidance commonly places many exercising adults around 1.4–2.0 g/kg/day.
The calculator’s activity and goal presets are planning ranges rather than universal requirements. Use a custom target when you are following guidance from a qualified dietitian, clinician, or coach.
Worked Example
Suppose a person weighs 80 kg and selects a protein target of 1.6 g/kg/day.
Daily protein = 80 × 1.6 = 128 g/day
Protein calories:
128 × 4 = 512 kcal/day
If the protein is divided across four meals:
128 ÷ 4 = 32 g per meal
If daily intake is 2,400 kcal:
512 ÷ 2,400 × 100 ≈ 21.3%
The estimated target is therefore 128 g of protein per day, averaging about 32 g per meal across four meals.
Important Notes
- Protein targets based only on body weight do not directly account for lean body mass or body composition.
- Higher protein intake does not automatically produce more muscle; resistance training, energy intake, recovery, and overall diet also matter.
- Protein can be distributed across meals according to preference and training needs; the per-meal result is simply the daily target divided evenly.
- The calorie-share result is meaningful only when the daily calorie input is reasonably accurate.
- Protein quality, food variety, fiber, micronutrients, carbohydrates, and healthy fats remain important parts of an overall diet.
- People with kidney disease, medically restricted diets, pregnancy-related nutrition needs, or other clinical conditions should follow individualized professional advice rather than a general calculator target.