An egg yolk weighs about 17 g. That is the answer: a large egg yolk weighs about 17 grams, which is a third of a large egg, and it holds all of the egg's fat, most of its calories, and most of its flavour. If a recipe calls for 3 yolks, that is about 51 grams. If it calls for 100 grams of yolk, that is about 6 yolks. This page gives you the table, the custard examples, and the reason yolks are weighed separately — because a custard is sensitive to the amount of yolk, and counting eggs is not precise enough.
The conversion table
| Egg yolks | Weight | Volume | Cups |
|---|---|---|---|
| 1 medium yolk | 14 g | 1 tbsp | 0.06 cup |
| 1 large yolk | 17 g | 1 tbsp + 1 tsp | 0.07 cup |
| 1 extra-large yolk | 19 g | 1 1/2 tbsp | 0.08 cup |
| 1 jumbo yolk | 22 g | 1 1/2 tbsp | 0.09 cup |
| 2 large yolks | 34 g | 2 tbsp + 2 tsp | 0.14 cup |
| 3 large yolks | 51 g | 1/4 cup | 0.21 cup |
| 4 large yolks | 68 g | 1/3 cup | 0.28 cup |
| 5 large yolks | 85 g | 6 tbsp | 0.35 cup |
| 6 large yolks | 102 g | 1/2 cup | 0.42 cup |
| 10 large yolks | 170 g | 3/4 cup + 1 tbsp | 0.70 cup |
The weight figures are approximate, because eggs vary in size. A large egg yolk is about 17 grams, and a cup of yolks weighs about 243 grams.
Worked example 1: a custard that needs 100 grams of yolk
A custard recipe calls for 100 grams of egg yolk and 500 grams of milk, which is the classic ratio for a crème anglaise. One hundred grams divided by 17 is 5.88, so separate 6 large eggs. If the scale reads 102 grams, that is close enough — 2 grams will not change the custard. If you only have medium eggs, whose yolks weigh 14 grams each, you will need 7 yolks, which is an awkward number, so separate 7 and pour off a little. The weight is the figure that matters, because the yolk is what thickens the custard, and a 10 percent error will make it either runny or too thick.
Worked example 2: a mayonnaise that needs 2 yolks
A mayonnaise recipe calls for 2 egg yolks, and you are making it by hand. Two yolks weigh about 34 grams, and they will emulsify about 250 ml of oil, which is a cup. If you use 3 yolks, the mayonnaise will be richer and thicker, and it will hold more oil — up to 375 ml. The yolk is the emulsifier, because it contains lecithin, which binds oil and water together, and the amount of yolk determines how much oil the mayonnaise can hold. That is why a recipe that calls for yolks by weight is more reliable than one that calls for them by count: a large yolk holds more oil than a medium yolk.
Worked example 3: a recipe that calls for yolks by count, scaled up
A recipe calls for 4 egg yolks, and you are tripling it for a party. Four yolks is about 68 grams, so a tripled recipe needs 12 yolks, which is about 204 grams. If you are scaling by weight, 204 grams is the figure to use, and it is more precise than counting eggs, because 12 large yolks might weigh 190 grams or 220 grams, and that 30-gram difference can change a custard. For a home recipe, counting is fine, but for a large batch, weigh them, and adjust by adding or pouring off a little yolk until the scale reads the right number.
Method and source
A large egg yolk is defined by weight: a large egg weighs about 50 grams without the shell, of which 33 grams is white and 17 grams is yolk. The figures come from the USDA, which grades eggs by weight: a medium egg yolk is about 14 grams, a large yolk is about 17 grams, an extra-large yolk is about 19 grams, and a jumbo yolk is about 22 grams. The yolk is about 50 percent water, 30 percent fat, and 16 percent protein, and it holds all of the egg's fat, most of its calories, and most of its vitamins. That is why the answer is "about 17 grams": it is an average, and individual yolks vary by a few grams in either direction, and by colour as well, depending on what the hen ate.
Practical guidance
Separate eggs when they are cold, because the yolk is firmer and less likely to break, and let the yolks come to room temperature before you use them in a custard or a mayonnaise, because cold yolks do not emulsify as well. Crack each egg into a small bowl before adding the yolk to the main bowl, so that a broken yolk does not ruin the whites you are saving. Use yolks the same day you separate them, or store them in a sealed container in the fridge with a little water on top to stop them drying out, and use them within two days. And when a recipe is precise — a custard, a mayonnaise, a hollandaise — weigh the yolks, because 17 grams is an average, and your eggs may be heavier or lighter.
Frequently asked questions
How many grams is an egg yolk?
An egg yolk weighs about 17 g for a large egg. A medium yolk weighs about 14 g, an extra-large yolk weighs about 19 g, and a jumbo yolk weighs about 22 g. The exact weight varies, so treat 17 g as an average.
How many egg yolks are in 100 grams?
There are about 6 egg yolks in 100 grams. One hundred grams divided by 17 is 5.88, so if a recipe calls for 100 grams of yolk, separate 6 large eggs.
How many cups is 100 grams of egg yolk?
One hundred grams of egg yolk is about 0.41 cups, or just over 1/3 cup. A cup of yolks weighs about 243 grams, so 100 divided by 243 is 0.41.
Does an egg yolk have fat?
Yes. All of the fat in an egg is in the yolk — about 5 grams of fat in a large yolk, along with about 55 calories. The white has no fat. That is why yolks enrich a custard and a sauce, and why whites whip into a foam while yolks do not.
How many calories are in an egg yolk?
A large egg yolk has about 55 calories, almost all of them from fat. A whole large egg has about 72 calories, so the yolk contributes most of the calories as well as all of the fat.
Can I freeze egg yolks?
Yes, but stir in a pinch of salt or sugar first, or the yolks will turn thick and gummy when they thaw. Freeze them in an ice-cube tray, one yolk per compartment, and use them within three months. Label the container, so you know whether you added salt or sugar.