Calorie estimates use the standard 4-4-9 rule: protein and carbs are counted at 4 calories per gram, and fat is counted at 9 calories per gram. You can compare foods either by their standard serving or by an equal 100 g basis, and the stacked view keeps those values aligned for faster scanning across the whole list. The Protein Absorption column uses approximate DIAAS reference values to compare protein quality, not just protein quantity. The 20g protein column estimates how many calories you would need from that food to reach 20 grams of protein. Values are approximate reference amounts and are best used for quick comparisons rather than precise nutrition tracking.