Brix to Specific Gravity

How to Convert Degrees Brix to SG?

To convert degrees Brix to specific gravity, use: SG = 1 + (°Bx / (258.6 - (°Bx × 227.1 / 258.2))). For a quick estimate: SG ≈ 1 + °Bx / 250. For example, 10°Bx equals approximately SG 1.040. This conversion is commonly needed when transferring refractometer readings into brewing software or recipes that use specific gravity. It is especially useful when following brew day targets written in SG while measuring with a refractometer. Many homebrewers take small hot-side samples during mash and boil, cool a few drops, and read Brix because it is faster and wastes less wort than filling a hydrometer jar. Converting those Brix values into SG makes it easier to compare against familiar gravity targets such as 1.040 for a lager, 1.050 for a pale ale, or 1.080 for an imperial stout. It also helps winemakers and cider makers move fruit-chemistry readings into the gravity language used by many fermentation trackers and ABV calculators. The same bridge is useful on pilot systems and cellar logs where the refractometer is the quickest instrument on hand, but the rest of the production workflow still expects SG numbers.

How to Convert Degrees Brix to Specific Gravity

1. Read the sugar concentration in degrees Brix from your refractometer.
2. Apply the conversion formula or use the quick estimate.
3. The result is the specific gravity.
4. Remember to temperature-correct your refractometer reading if it is not ATC (automatic temperature compensation).

Real-World Examples

History of Degrees Brix and Specific Gravity

Refractometers became popular in homebrewing during the 2000s as affordable digital and optical models became available. They offered a major advantage over hydrometers: only a few drops of wort were needed instead of a full test jar, and readings were instant. The main disadvantage — inaccuracy in the presence of alcohol — led to the development of widely-used correction formulas by brewing researchers.

Common Mistakes to Avoid

• Forgetting that refractometer Brix readings are only directly valid for unfermented wort. Once fermentation begins, alcohol skews the reading.
• Not accounting for temperature. Refractometers calibrated at 20°C will give slightly off readings at other temperatures unless they have ATC.
• Assuming 1°Bx always equals exactly four gravity points. That shortcut is close around ordinary-strength wort but becomes less accurate as Brix increases.
• Entering a raw fermented-beer Brix reading into brewing software as if it were wort SG. Always apply an alcohol correction first or use a hydrometer for finished beer.

Frequently Asked Questions