💧 Gravity Dilution Calculator
Enter your current volume and gravity and a target gravity to see how much water to add.
Water to add
4 L
Final volume
24 L
If your wort came out stronger than planned, adding water dilutes it. This uses gravity points (the last two digits of the SG): points × volume is conserved, so water to add = current volume × (current points ÷ target points − 1). Add water gradually and re-measure — and remember diluting also lowers the bitterness and colour, not just the gravity. 🔒 In your browser.
How the gravity dilution calculator works
If your wort finished stronger than the recipe called for, adding water dilutes it to the gravity you want. The tool uses gravity points (the last digits of the specific gravity): the total points are conserved when you add water, so it solves for the final volume that gives your target gravity and tells you how much water that means adding.
Add the water gradually and re-measure as you go — it's easy to overshoot, and you can't easily undo it. Remember that diluting lowers everything proportionally, not just the gravity: the bitterness (IBU), colour and flavour intensity all drop too, so a big correction can leave the beer tasting thin.
Frequently asked questions
How much water do I add to lower gravity?
Water to add = current volume × (current gravity points ÷ target points − 1), where points are the last two SG digits. To take 20 L of 1.060 down to 1.050: 20 × (60 ÷ 50 − 1) = 4 L. The tool computes it for you.
How does diluting wort work?
Gravity points × volume stays constant when you add water, so spreading the same sugar over more liquid lowers the gravity. It's the same principle as any dilution — more solvent, lower concentration.
Does adding water change anything besides gravity?
Yes — it dilutes everything. Bitterness, colour and flavour all drop in the same proportion as the gravity, so a large dilution can make the beer taste watery. Correct in small steps and taste as you go.
My original gravity is too high — what should I do?
Top up with clean, sanitised water (or cooled boiled water) to the volume this tool gives, mixing and re-measuring. Catching it before fermentation is easiest; adjusting later dilutes the finished beer.
Can I use this to raise gravity?
Not directly — this tool dilutes. To raise gravity you'd boil longer to evaporate water, or add malt extract; a target above the current gravity isn't achievable by adding water.