Dilution And Boiloff Gravity Calculator - Brewer's Friend
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Dilution and Boil Off Gravity Calculator

Calculates how much you need to dilute or boil down your wort volume to hit a certain gravity. Helps you hit the correct wort volume and target gravity for your home brewed beer!

There are two ways to look at this, which is why there are two calculators below.

1) The target gravity is known, the new volume is unknown:
Finds New Volume:
Wort Volume: (gal / L / qt)
Current Gravity:
Desired Gravity:

New Volume:

2) The target volume is known, the new gravity is unknown:
Finds New Gravity:
Wort Volume: (gal / L / qt)
Current Gravity:
Target Volume: (gal / L / qt)

New Gravity:
Reports the new volume in the same units the current volume was provided in.

If the new volume is above the current volume, top off with water (only use water you know is from a clean source, such as bottled spring water, water you prepared in advance). Tap water is okay, but often contains a little chlorine which you may notice in your beer.

If the new volume is below the current volume, boil the wort to evaporate some of the current volume.

Thanks for using our calculator. You might be interested in the Complete Recipe Builder. Recipes can be saved, printed, shared, and brewed for complete record keeping.

Click Here To Try The Complete Recipe Calculator