Mead Must Calculator
Enter your batch size, the ABV you are aiming for and how sweet the finished mead should be, and get the honey weight, the water to top up with, and the gravity to hit.
Results
- Water to top up
- 15 L
- Original gravity
- 1.093
- Expected final gravity
- 0.998
Staggered nutrient additions keep mead yeast healthy through a long, high-gravity ferment - the yeast nutrient calculator sizes a TOSNA-style schedule from this must's honey load.
How the must math works
Original gravity comes from the target ABV with a small allowance for what stays unfermented: about 0.25% ABV of extract for a dry finish, about 2% for a semi-sweet finish at 1.015. Gravity points convert to sugar demand at roughly 2.61 g of sucrose per point per liter, and honey is about 80.5% fermentable sugar at roughly 1.42 kg per liter, so honey grams = sugar grams / 0.805. The water is simply the batch volume minus the volume the honey displaces.
Once the must is mixed, the yeast nutrient calculator builds the staggered feeding schedule from the honey load, and the general ABV calculator checks the finished gravity against the target.
Frequently asked questions
What original gravity should my mead start at?
Divide your target ABV by 131.25 and add 1: about 1.093 for a 12% dry mead, 1.107 for 14% semi-sweet. A hydrometer reading of the mixed must is the ground truth - stir until the honey is fully dissolved and the sample is representative before trusting the number.
Why does honey amount not scale in a straight line?
It nearly does: each gravity point needs about 2.61 g of sugar per liter, and honey delivers that sugar at about 80.5% by weight. The one wrinkle is volume - honey displaces roughly 0.7 ml per gram, so the water top-up shrinks as the honey bill grows, and very high gravity musts end up mostly honey.
Should I heat or raw-add the honey?
Modern mead practice favors no boil: dilute and mix the honey in cool, chlorine-free water, because boiling drives off aroma and can haze the must. If the honey carries wax or debris, strain it; if you worry about wild microbes, a Campden tablet at must-making time handles that without cooking the flavor.