Daily Protein Requirement Calculator

Protein Calculator Form

Age

Sex

Physiological Status

Body Weight

Weight Unit

Height

Height Unit

Body Fat % (optional)

Activity Level

Training Type

Nutrition Goal

Reference Basis

Calculation Method

Manual Multiplier (g/kg)

Meals Per Day

Formula Used

Weight in kilograms = pounds × 0.453592

Lean body mass = body weight × (1 − body fat % ÷ 100)

Protein range = reference mass × selected g/kg multiplier range

Target protein = reference mass × midpoint multiplier in automatic mode

Protein per meal = target protein ÷ meals per day

Protein calories = target protein × 4

BMI = weight in kilograms ÷ height in meters²

Automatic mode starts from activity level, then raises the range when training, fat loss, muscle gain, recovery, older age, pregnancy, or lactation require more support.

When lean mass is selected, the calculator uses lean body mass only if body fat percentage is available.

How to Use This Calculator

Enter age, weight, height, and your preferred units.
Optional: add body fat percentage for lean-mass-based estimates.
Select your activity level, training style, and main goal.
Choose whether calculations should use total body weight or lean mass.
Use automatic mode for guided ranges or manual mode for a fixed g/kg target.
Set how many meals you usually eat each day.
Press the calculate button to view results above the form.
Review the chart, notes, per-meal target, and export options.

Example Data Table

Profile	Weight	Activity	Goal	Basis	Suggested Range	Target
Office worker	70 kg	Moderate	Maintenance	Body weight	84.0–105.0 g	94.5 g
Gym trainee	82 kg	Active	Muscle gain	Body weight	131.2–180.4 g	155.8 g
Runner in recovery	60 kg	Moderate	Recovery	Body weight	84.0–120.0 g	102.0 g
Fat-loss plan	95 kg	Light	Fat loss	Lean mass, 28% body fat	109.4–164.2 g	136.8 g

Frequently Asked Questions

1) Which unit should I enter for weight and height?

Use whichever unit is easiest for you. The calculator converts pounds to kilograms and inches to centimeters automatically before applying the protein formulas.

2) Why do protein needs change with goals?

Maintenance usually needs less protein than muscle gain, fat loss, or recovery. Hard training and calorie deficits often increase protein needs to better preserve or build lean tissue.

3) Is more protein always better?

Not always. Very high intakes may offer little extra benefit once needs are covered. Balanced meals, total calories, training quality, and food variety still matter greatly.

4) Should I use body weight or lean mass?

Body weight works well for many people. Lean mass can be useful when body fat is known, especially during fat-loss planning or when you want a more individualized target.

5) How much protein should I eat per meal?

A simple starting point is the calculator’s per-meal target. Spreading protein across three to five meals often helps consistency, appetite control, and workout recovery.

6) Do older adults usually need more protein?

Often yes. Aging can reduce how efficiently the body uses protein. Many older adults benefit from a slightly higher intake, especially with resistance training or recovery needs.

7) Can this calculator be used during pregnancy or lactation?

Yes, it includes supportive adjustments for pregnancy and lactation. Still, personal medical guidance is best because total calorie needs, symptoms, and clinical context can change recommendations.

8) Is this tool a medical diagnosis?

No. It is an educational estimator. For kidney disease, eating disorders, clinical nutrition therapy, or pregnancy complications, use professional medical advice.