From 500 to 800 kcal: what is calculated
When scaling an entire recipe, the factor is 800 ÷ 500 = 1.6. A 100 g ingredient becomes 160 g before rounding. Calories and macros are then recalculated from the resulting amounts. Replacing an ingredient also changes its nutritional composition.
The energy target is an estimate reviewed through tracking. Brand, preparation, raw or cooked weight and food-composition data affect the result. A consistent calculation does not mean knowing your body’s needs exactly.