Egg Size Converter

The short answer

Recipes mean large eggs unless they say otherwise. If you have medium eggs instead, four large becomes 5 medium. One or two eggs, and you can usually just swap them one for one — the sizes only pull apart once the count climbs.

USDA egg weight classes

This is the table everything here is built on. The number that defines a size is the minimum net weight of a dozen — not how big any one egg looks.

Weight classes as published by the USDA Agricultural Marketing Service standard for shell eggs. The per-egg columns are that dozen weight divided by twelve. "Min single egg" is USDA's floor for individual eggs within a dozen, which stops a carton being padded with undersized eggs — the standard sets none for peewee.

How this works

Egg sizes are a weight grade, and that is the thing almost nobody realises. USDA does not measure an egg's dimensions or judge how big it looks in the carton — it weighs the dozen. A carton is "large" because those twelve eggs weigh at least 24 oz together. The standard even allows a lot average of 3.3% of the eggs to fall into the next class down, so a large carton is genuinely allowed to contain a few mediums.

Because the classes are just weights, converting between them is just arithmetic. They sit 3 oz per dozen apart — a tidy quarter-ounce per egg — from peewee at 15 oz a dozen up to jumbo at 30. So a large egg is 2 oz and a medium is 1.75 oz, and swapping one for the other means finding the count that gets you back to the same total weight. That is all this converter does: multiply, divide, round to a whole egg.

Rounding is where judgement creeps in, and it turns out none is needed. Rounding to the nearest whole egg reproduces the American Egg Board's published conversion chart exactly — all twenty-four of its cells, from "1 large = 1 medium" to "6 large = 8 small". We assert that chart in our tests, so if the arithmetic here ever drifts from the industry's own table, the build fails.

The one thing weight classes cannot tell you is what is inside. Shell is about 11% of an egg, per USDA's Egg-Grading Manual, which puts white at 58% and yolk at 31%. So a large egg — 2 oz in the shell — is about 50 g of actual egg. That is worth knowing because it is also the escape hatch: crack your eggs into a bowl, beat them, and weigh out what you need. Size classes stop mattering entirely, which is a gift if your flock lays a carton of six different eggs.

Does any of this matter? For one or two eggs, rarely — swap them and move on. It compounds, though. Six small eggs where a recipe wanted six large is 9 oz of egg instead of 12, and a quarter of the egg missing from a cake batter shows up as a drier, tighter crumb. Custards, meringues, and anything where egg is the structure are the least forgiving. Scrambled eggs could not care less.

A worked example

A cake recipe calls for 4 large eggs and your hens have laid you a basket of mediums. Four large is 4 × 2 oz = 8 oz of egg. A medium is 1.75 oz, so you need 8 ÷ 1.75 = 4.57 mediums — call it 5. Use four and you are an egg short of the batter the recipe was tested with; use five and you are within a rounding error. If you would rather be exact, beat five mediums in a jug and pour off 202 g.

Frequently asked questions

What size eggs do recipes mean?

Large, unless the recipe says otherwise. The American Egg Board is explicit that large is the standard used in most recipe development, so "2 eggs" in a US cookbook means two large eggs — about 4 oz in the shell. Substituting a different size without adjusting can affect texture and consistency, which is what this converter is for.

How many medium eggs equal 2 large eggs?

Two. Two large eggs weigh about 4 oz, and a medium egg is about 1.75 oz, so the exact answer is 2.3 medium — close enough to just use two. The sizes only pull apart once you need more eggs: at four large you need five medium, and at six large you need seven.

What do the USDA egg sizes actually mean?

They are minimum weights per dozen, not measurements of any single egg. USDA sets jumbo at 30 oz per dozen, extra large at 27, large at 24, medium at 21, small at 18 and peewee at 15. Size says nothing about how big an egg looks — it is the weight of the whole dozen that puts a carton in a class, and the standard even allows a small share of eggs from the next class down.

Why are my backyard eggs all different sizes?

Because you don't have a grading machine, and because your hens are individuals. Pullets lay small eggs when they start and work up to their full size over a few months; older hens lay larger eggs but fewer of them. Breed matters too. A carton from a supermarket is sorted by weight from thousands of birds — a carton from your run is whatever the flock produced that week.

Can I just weigh my eggs instead?

Yes, and for baking it is the better answer. Crack your eggs into a bowl, beat them, and weigh out what the recipe needs. USDA's Egg-Grading Manual puts the shell at about 11% of an egg's weight, so a large egg is roughly 50 g of actual egg — and 50 g is exactly what USDA lists as one large egg's edible portion. Weighing sidesteps size classes completely, which is how you get consistent baking out of an inconsistent flock.

Does egg size change the baking result much?

For one or two eggs, rarely. For four or more the error compounds — swapping six small eggs for six large loses about 3 oz of egg, which is a real difference in a cake batter and shows up as a drier, tighter crumb. Custards, meringues and anything where egg is the structure are the least forgiving. Cookies and scrambled eggs will not care.