Hydrometer
Specific Gravity
At the fermentation stage, a hydrometer is the #1 most important tool. It's the device that will give you an insight into how well the fermentation process is coming along, and whether your cider, beer, mead or wine is ready.
Use at the start (SG - Specific Gravity) & again near the end (FG - Final Gravity) of your brew.
The basic formula: ABV = (OG - FG) * 131.25
ABV = alcohol by volume, OG = original gravity, & FG = final gravity.
This formula for a beer having an OG of 1.055 & a FG of 1.015, your ABV would be 5.25%.
1.055 -1.015 = 0.04 so 0.04 x 131.25 = 5.25%
An absolute must have for any brewer, amateur to professional. It's recommended that you always have 2 Hydrometers on hand.
Suspend the Hydrometer in a sample of your wort to get the reading in one of our 250mL Glass Cylinders or our 100mL Plastic Cylinder.