Must & Honey — Sugar & Alcohol Calculator

About this calculator

Since I started making wine at home, I've been fascinated by the science behind fermentation. This calculator helps estimate how much sugar to add to your must and predicts the potential alcohol content once fermentation is complete.

Keep in mind that this tool provides estimates based on typical fermentation behavior. Actual results may vary depending on yeast strain, fermentation conditions, and other factors.

How it works

This calculator uses the relationship between specific gravity (SG), Brix, and alcohol by volume (ABV) to estimate how much sugar to add to your must. The formulas are based on standard winemaking principles:

Brix from SG: Converts specific gravity to degrees Brix, which represents the sugar content of the must.
Target ABV from SG: Estimates the potential alcohol content based on the difference between initial and desired specific gravity.
Target SG from ABV: Calculates the desired specific gravity needed to achieve a target alcohol percentage.

By entering your initial SG and either a desired SG or target ABV, the calculator will provide you with the amount of sugar to add and the expected final alcohol content.

Desired SG	Brix	Potential ABV	Wine Type
1.060	14.7	7.88%	Light fruit wine or low alcohol base
1.075	18.2	9.84%	Light white, rose, or sparkling base
1.090	21.6	11.81%	Standard dry table wine must
1.100	23.8	13.13%	Fuller red or richer white must
1.115	27.0	15.09%	Dessert or high-gravity must
1.130	30.2	17.06%	Very high sugar must

Desired SG

Brix

Potential ABV

Wine Type

1.060

14.7

7.88%

Light fruit wine or low alcohol base

1.075

18.2

9.84%

Light white, rose, or sparkling base

1.090

21.6

11.81%

Standard dry table wine must

1.100

23.8

13.13%

Fuller red or richer white must

1.115

27.0

15.09%

Dessert or high-gravity must

1.130

30.2

17.06%

Very high sugar must

Notes

How to use a Hydrometer

Sanitize the hydrometer and test jar before taking a reading.

Retrieve a sample of the must before adding sugar or yeast and transfer to the test jar.

Gently lower the hydrometer into the liquid, ensuring it floats freely without touching the sides.

Spin the hydrometer gently to release bubbles, then read the scale at the bottom of the liquid's meniscus.

Record the reading as your initial specific gravity (SG). Always take reading at eye level.

Label the test jar with the date and type of must for future reference.

Let the wine ferment according to your recipe, taking additional hydrometer readings as needed to monitor progress.

After fermentation is complete, take a final hydrometer reading to determine the final specific gravity (FG) and calculate the alcohol content.

Use your final and initial readings to calculate the alcohol content of your wine.

Always clean and store your hydrometer properly after use to ensure accurate readings in the future.

Appendix

Conversion Tables

Specific Gravity	ABV	Brix
0.980	-2.6%	-5.3
0.985	-2.0%	-3.9
0.990	-1.3%	-2.6
0.995	-0.7%	-1.3
1.000	0.0%	0.0
1.005	0.7%	1.3
1.010	1.3%	2.6
1.015	2.0%	3.8
1.020	2.6%	5.1
1.025	3.3%	6.3
1.030	3.9%	7.5
1.035	4.6%	8.7
1.040	5.2%	10.0
1.045	5.9%	11.2
1.050	6.5%	12.3
1.055	7.2%	13.5
1.060	7.8%	14.7
1.065	8.5%	15.8
1.070	9.1%	17.0
1.075	9.8%	18.1
1.080	10.4%	19.2
1.085	11.1%	20.4
1.090	11.7%	21.5
1.095	12.4%	22.6
1.100	13.0%	23.7
1.105	13.7%	24.8
1.110	14.3%	25.8
1.115	15.0%	26.9
1.120	15.6%	28.0
1.125	16.3%	29.0
1.130	16.9%	30.1
1.135	17.6%	31.1
1.140	18.2%	32.2
1.145	18.9%	33.2
1.150	19.5%	34.2
1.155	20.2%	35.3

Temperature (F)	SG Correction
52.2	-0.0001
60.0	0.0000
66.6	+0.0001
72.4	+0.0002

Temperature (F)	Brix Correction
52.2	-0.2
60.0	0.0
66.6	+0.2
72.4	+0.4