We have 5 acres total - includes the land the house and the barn are on. Not sure the exact size of the pastures but we have one larger back pasture, a bit smaller side pasture, and then two front small lots we use to rotate them on. We also have a dry/mud lot area to keep the horses up out of the back fields if its too wet so they don't get torn up.
Live on 3 acres, have 1 acre separated into three smaller pastures that get rotated, one of which is a sacrifice lot, and the rest of the 2 acres of yard and woods is free for pasture as long as the kids and horse get along during the day xD
About two acres, but it's not very good grass. I have access to 10 or so across the road -- all I have to do is fence it. I did last year, but not this year. Will have to do it next year. My pastures are tired.