One large egg is generally equivalent to one small egg if you are using just one egg in a recipe. However, if you need to replace multiple large eggs with small eggs, the substitution changes slightly. For example, 2 large eggs can be replaced with 3 small eggs; 3 large eggs with 4 small eggs; 4 large eggs with 5 small eggs; and 5 large eggs with 7 small eggs. The key is that for a single large egg, one small egg can work as a substitute, but when more eggs are needed, slightly more small eggs are required to equal the volume of large eggs.
In terms of volume, one large egg yields roughly 3 tablespoons of liquid egg, so you can measure and adjust accordingly if precision is needed. But as a quick rule, for just one egg substitution, one small egg will suffice for one large egg.
