Convert hydrometer readings between all popular scales: Balling (Blg), Brix, Plato, specific gravity SG, Oechsle, Baumé and KMW. You will also see the sugar content in g/l and the potential strength of wine.
Hydrometer or refractometer?
A hydrometer measures density and works throughout fermentation but needs a larger sample. A refractometer needs a few drops and shows °Brix, but once fermentation starts the alcohol distorts the reading and a correction is needed. For washes and wines a Blg hydrometer is the most practical.
Which scale for what?
In Poland the Balling (Blg) scale is the most popular. You will find Brix on refractometers, Plato in brewing, SG in English recipes, Oechsle in German and KMW in Austrian winemaking. Blg, Brix and Plato express practically the same thing – percent sugar by mass.
How we calculate
Blg, Brix and Plato are practically the same scale (% sugar by mass). SG = 1 + P / (258.6 − 227.1 × P / 258.2), Oechsle = (SG − 1) × 1000, Baumé = 145 − 145 / SG. KMW (Klosterneuburg) is approximate: ≈ °Oechsle / 4.86.
Frequently asked questions
Is Blg the same as Brix?
In practice, yes – both scales express the percentage of sugar by mass. The differences are below the accuracy of home hydrometers.
Does temperature affect the hydrometer reading?
Yes. A hydrometer is calibrated for a specific temperature (usually 20°C – check the scale). For an accurate result cool or warm the sample to that temperature.
What is 1°Blg?
1°Blg means 1 g of sugar in 100 g of solution, i.e. about 10 g of sugar per litre of must or wash.
How do I convert SG to Blg?
Approximately °Blg ≈ (SG − 1) × 250, e.g. SG 1.080 ≈ 20°Blg. The calculator uses a more accurate polynomial formula.