Dairy & Eggs
Egg Yolk Conversion
Egg Yolk weighs 243g per US cup.
Typically measured per-egg (~18g each) rather than by the cup.
| Amount | Grams | Ounces |
|---|---|---|
| 1 cup | 243.0 g | 8.57 oz |
| 1/2 cup | 121.5 g | 4.29 oz |
| 1/4 cup | 60.8 g | 2.14 oz |
| 1 tbsp | 15.2 g | 0.54 oz |
| 1 tsp | 5.1 g | 0.18 oz |
| 100 g | 100.0 g | 3.53 oz |
Need a different amount? Use the full Ingredient Converter tool.
Egg yolk weighs 243 grams per cup as a bulk figure, but like egg white it's overwhelmingly measured per egg in real recipes — about 18 grams per US large egg — since a recipe built around yolks (custard, hollandaise, mayonnaise) typically specifies a number of yolks rather than a cup volume.
Yolk carries essentially all of an egg's fat and most of its vitamins and minerals, along with lecithin — a natural emulsifier that's exactly what lets a yolk-based sauce like hollandaise or mayonnaise hold oil and water together in a smooth, stable emulsion that would otherwise separate, a genuinely different structural job than the air-trapping whipping egg whites do.
Because yolks are so fat- and protein-rich, they're more prone to forming a tough, rubbery "skin" or setting into an unusable gel if frozen without protection — this site's storage guidance specifically notes whisking in a pinch of salt or sugar before freezing raw yolks, a real, necessary step to keep them workable after thawing that egg whites don't require.
A single large egg yolk weighs about 18g, and this site's cup figure (243g) mainly serves recipes working from a large batch of separated yolks — yolks contain nearly all of an egg's fat and are what give custards, curds, and rich cake batters their signature silky texture, a role egg whites alone can't replicate.
Egg yolks also contain lecithin, a natural emulsifier that helps bind fat and water together in a sauce like hollandaise or mayonnaise — a specific functional property that has nothing to do with the yolk's weight or richness alone, but is exactly why those sauces depend on yolks rather than whole eggs.
How long does it last?
Storage & shelf life →
Frequently asked questions
How much does a single egg yolk weigh?
About 18 grams for a US large egg — the figure most relevant to actual cooking, since recipes built around yolks (custard, hollandaise, mayonnaise) almost always specify a number of yolks rather than a bulk cup measurement.
Why does mayonnaise specifically need egg yolk rather than whole egg?
Yolk contains lecithin, a natural emulsifier that lets oil and water bind into a smooth, stable mixture rather than separating — egg white lacks this emulsifying capacity, which is why yolk-based sauces like mayonnaise and hollandaise rely on yolks specifically.
Why do egg yolks need salt or sugar added before freezing, but egg whites don't?
Yolks carry enough fat and protein that freezing and thawing them untreated causes that structure to gel into a thick, rubbery mass — a small amount of salt or sugar stirred in beforehand interrupts that gelling and keeps the texture usable, a precaution egg white's leaner composition simply doesn't need.
How long do separated egg yolks last in the fridge?
About 2 days after separating — shorter than egg whites' 2-4 day window, since yolks are more nutrient-dense and support bacterial growth more readily once the shell's protection is removed.
Can I use just the yolk if a recipe calls for a whole egg?
Not as a direct substitute — a whole egg's white contributes real structure and moisture that yolk alone doesn't replace, so using only yolk changes a recipe's texture and volume in ways beyond just richness.