Refractometer Calculator

Correct refractometer readings during fermentation

Refractometer Readings

Alcohol affects refractometer readings. This correction is needed for accurate FG values during and after fermentation.

Reading before fermentation

Reading during/after fermentation

Corrected Final Gravity
1.012
SG
1.048
OG (SG)
4.7%
ABV
3.1
°Plato
About the Correction

This calculation uses the Sean Terrill formula to correct refractometer readings. Alcohol has a different refractive index than sugar water, which is why uncorrected values appear too high during fermentation.

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