How can I determine what my specific gravity will be using malt extract?

Dry malt extract (DME) produces about 44 degrees per pound per gallon of water and liquid malt extract produces about 35 °.

To determine how much malt extract to use to reach a predetermined starting gravity, use this simple formula: (degrees of extract) x pounds of malt used by gallons of beer to be brewed. For example, if we use 6 pounds of liquid malt extract to make 5 gallons of beer, we would have 35 x 6 = 210... so, 210 divided by 5 (gallons of beer to be brewed) = 42, or a starting gravity of 1.042.