Charles Spurgeon Commentary Exodus 16:13-16

"And it came to pass at even, that the quails came up, and covered the camp: and in the morning the dew lay round about the camp. And when the dew that lay was gone up, behold, upon the face of the wilderness a small round thing, small as the hoar-frost on the ground. And when the children of Israel saw it, they said one to another, What is it? For they knew not what it was. And Moses said unto them, It is the bread which Jehovah hath given you to eat. This is the thing which Jehovah hath commanded, Gather ye of it every man according to his eating; an omer a head, according to the number of your persons, shall ye take it, every man for them that are in his tent." — Exodus 16:13-16 (ASV)

And it came to pass, that at even the quails came up, and covered the camp: and in the morning the dew lay round about the host. And when the dew that lay was gone up, behold, upon the face of the wilderness there lay a small round thing, as small as the hoar frost on the ground. And when the children of Israel saw it, they said one to another, It is manna: for they wist not what it was. And Moses said unto them, This is the bread which the LORD hath given you to eat. This is the thing which the LORD hath commanded, Gather of it every man according to his eating, an omer for every man,

About two pints and a half, I think; according to some calculations, two quarts, or thereabouts. There would be more sustenance in it than in a half-quarter loaf of bread per day: An omer for every man.