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Gravity Dilution Calculator
Calculate how much water to add to dilute your wort or beer to a target gravity. Also useful for calculating boil-off rates and pre-boil volumes.
Original or current specific gravity
Desired specific gravity after dilution
Formula
Final Volume = (Current Volume × Current GP) ÷ Target GPWhere GP (Gravity Points) = (SG - 1) × 1000
About Gravity Dilution
This calculator helps you determine how much water to add to dilute wort or beer to a target gravity. It's based on the principle that the total amount of extract (sugar) remains constant during dilution.
Common Uses:
- High Gravity Brewing: Brew concentrated wort and dilute to target strength at packaging
- Correcting Overshoots: Fix batches that came out stronger than intended
- Pre-Boil Calculations: Determine pre-boil volume needed to hit target post-boil gravity
- Parti-Gyle Brewing: Calculate dilution for different strength beers from the same mash
Important Considerations:
- Use deoxygenated, sterile water when diluting finished beer to avoid oxidation and contamination
- Consider the impact on hop character - IBUs and hop flavor will be diluted proportionally
- Account for any dissolved CO₂ when diluting carbonated beer
- Temperature affects volume - measurements should be taken at the same temperature
Reverse Calculation (Boil-Off):
You can also use this calculator in reverse to determine boil-off. Enter your pre-boil volume and gravity as "current" values, and your target post-boil gravity. The "water to add" will be negative, showing the volume you need to boil off.