Dilution to Target Gravity

About this calculator

When a batch of wort, must or wash comes out with a higher specific gravity than the recipe calls for, brewers dilute it with water to bring the gravity down to target, using the relationship that gravity above 1.000 is roughly proportional to the mass of dissolved sugar: (current gravity − 1) × current volume ≈ (target gravity − 1) × final volume, which can be solved for how much water to add.

This comes up constantly in homebrewing and winemaking when the boil-off runs longer than expected and concentrates the wort more than planned, or when a must from very ripe fruit starts too sweet — diluting to the target original gravity keeps the final alcohol content and flavor balance where the recipe intended, rather than leaving you with a stronger, sweeter or more overpowering finished product.

This calculator takes your current gravity, current volume and target gravity, and tells you how much water to add to hit your target.