Brix to SG Calculator
Enter a Brix or SG value and get the other side instantly, plus Plato. Brix readings are accurate for unfermented wort and must - alcohol distorts them in finished beer.
Conversion
- Brix (°Bx)
- 12.01 °Bx
- Plato (°P)
- 12.01 °P
How the conversion works
One degree Brix is 1 gram of sucrose per 100 grams of liquid. The calculator converts Brix to SG with the brewer's standard formula SG = 1 + Bx ÷ (258.6 - 0.8796 × Bx) and inverts it numerically for the reverse direction. One degree Plato is nearly identical to one degree Brix - within 0.03 °P across the brewing range.
Working from a hydrometer instead? Correct it for sample temperature with the hydrometer temperature correction tool, then turn the corrected pair into alcohol with the ABV calculator.
Frequently asked questions
Why does my refractometer read wrong after fermentation starts?
Refractometers are calibrated for sugar dissolved in water. Once yeast has produced alcohol, the alcohol distorts the refractive index, so the reading drifts away from the true gravity - often showing 1-2 Brix high mid-ferment and more when finished. Use a hydrometer for final gravity, or apply an alcohol correction formula to the refractometer reading.
Is Brix the same as Plato?
Practically yes for brewing: both express the percentage by mass of dissolved sugar. They use slightly different reference tables, but across the normal brewing range they agree within about 0.03 degrees Plato. Wine makers use Brix, German brewers use Plato, and this calculator shows both.
What Brix should my starting wort or must be?
A typical 1.050 beer wort sits around 12.4 Brix, wine must between 20 and 25 Brix, and kombucha starts near 5-6 Brix before fermentation. Multiply your target Brix by roughly 4 to get an approximate SG, or use this calculator for the exact value.
How do I convert a mid-fermentation refractometer reading?
Take the Brix reading and apply a correction that accounts for the alcohol produced so far - the common formulas need both the original and current reading. As a rule of thumb, subtract about 1.5-2 Brix from the raw number once fermentation is active, but for racking or packaging decisions confirm with a hydrometer.