I was searching for some things and ran across that there's a difference of the two, which might be dumb, but I had no clue. So my question is the OG higher or lower pre-boil?
Pre-boil will be lower OG. During the boil, you'll lose a lot of water to evaporation, leading to a more concentrated wort -- hence a higher OG post-boil.
Makes sense, thank you.
Pre-boil should be a lower gravity than post-boil.
As the water boils off, the density of sugars increases raising the gravity.