I've been driving myself a bit crazy... I created a bug for ginger beer, then made up the mix of sugar lemon etc and left it to do its thing in a carboy for a week. Bubbled nicely, bottled, let sit for another week in bottle ... Light and thin, super bubbly, defo alch flavor ( I used champagne yeast) ... But ...

Initial gravity is higher than final. I let the bubbles die down and it levels to the same as the initial.

I researched and feel I'm using the hydrometer correctly, but can't find any reason other than changing the mix after initial reading could throw out a false reading ... I did nothing to change the brew

I am a newby...

Any ideas?

  • 3
    I don't understand your question: the original gravity (OG) - or as you call it the initial gravity - is always higher than the final gravity (FG). Jun 17, 2018 at 7:55

1 Answer 1


I suppose that you are thinking that measuring the gravity, is the same as measuring the alcohol in the ferment? That is not the case, what you are measuring is the sugar in the solution.

At the start there is more sugar, your original gravity (OG) has a certain value. At the end of the fermentation, an amount of sugar has been fermented by the yeast into carbon dioxide and alcohol. Then you measure the final gravity (FG). From this you calculate the amount of alcohol in your ferment.

A simple formula is: ABV = 131.25*(OG - FG)

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