Portion Size Calculator

Culinary scaling allows home cooks, meal-preppers, and commercial caterers to resize any standard recipe without altering taste, texture, or macro ratios. The fundamental conversion factor is the Recipe Conversion Factor (RCF), defined as the target number of servings divided by the original base servings.

Formula: Recipe Conversion Factor (RCF) = Target Servings / Base Servings; Scaled Quantity = Original Quantity × RCF

• RCF: Multiplier applied to all scalable base ingredients
• Original Quantity: Weight, volume, or count of the ingredient in the source recipe
• Scaled Amount: Required ingredient amount for the desired yield
• Portion Weight: Finished plate weight per individual guest or diner

• Dinner for 4 Scaled to 10 Guests: RCF = 10 / 4 = 2.5; 600g chicken breast × 2.5 = 1,500g; 400g rice × 2.5 = 1,000g = 2.5x Scaling Factor (2,500g total cooked food at 250g per serving)
• Single Meal Prep (1 Serving to 7 Days): RCF = 7 / 1 = 7.0; 150g protein × 7 = 1,050g; 100g carbs × 7 = 700g; 150g veggies × 7 = 1,050g = 7.0x Batch Multiplier (2.8 kg total batch weight)

While bulk ingredients (flour, meats, vegetables, liquids, grains) scale strictly linearly, seasonings and leavening agents require caution. Salt, chili, alcohol, baking soda, and strong spices should be scaled at approximately 1.5x to 1.75x when doubling a recipe, rather than an automatic 2.0x, to prevent overpowering dishes or creating alkaline chemical imbalances.

A standard dietary portion (as defined by USDA MyPlate and the FDA) differs significantly from typical restaurant portions. A standard cooked meat serving is 85g to 115g (3 to 4 oz, size of a deck of cards), cooked grains/pasta is 150g to 200g (1/2 to 1 cup), and vegetables are 150g to 200g per meal.