Using a hydrometer

[steturbo]

I am trying to work out how to the ABV of beer i have been watching videos on you tube about it and my head now hurts, all that I have picked up is get the reading before and after take away the lower reading from the higher then with the answer decide that by 7.36

Eg 1.090-1.010= 0.080
0.0.80 divide by 7.36 = ABV 0.010

It doesn't seem right to me

Please explain in stupid terms so I understand

 

[hunter_le five]

Seems like a decimal point must be off somewhere. ABV should be ~10.5% (0.105), not 0.010.

I would take the guesswork and human error out and just use one of the many free online ABV calculators.

Edit: looks like the standard formula is [ABV = (og – fg) * 131.25], but I noticed using your formula if you instead divide by .736 (instead of 7.36) it should get you close. (1/.736 x 100 = 135.87)

 

[ncboiler]

Estimated ABV = (OG - FG)*131