🔬 Brix to Specific Gravity Converter
Enter a Brix or specific-gravity value to convert between the two, the scales refractometers and hydrometers use.
Specific gravity
1.048
°Brix (≈ °Plato)
12.0
°Brix (and the near-identical °Plato) measures dissolved sugar as a percentage by weight; specific gravity measures density relative to water. Refractometers read in Brix, hydrometers in gravity. This converts between them using the standard cubic formulas. Note: on fermenting or finished beer, alcohol skews refractometer Brix, so use the refractometer correction tool for final gravity. 🔒 In your browser.
How the brix to specific gravity converter works
Refractometers read sugar content in °Brix (percent sugar by weight), while hydrometers read specific gravity (density relative to water). The tool converts between them with the standard cubic formulas used across brewing software, in whichever direction you need, Brix to gravity or gravity to Brix. The relationship is not a simple constant multiplier: a sugar solution gets denser faster than its weight-percent rises, which is why the conversion uses a cubic polynomial rather than a straight line. A rough rule of thumb some brewers use is that gravity points are about Brix × 4 (12 °Brix ≈ 48 points, i.e. 1.048), but the full formula is more accurate across the range.
This conversion is for sugar solutions like unfermented wort or must. Once fermentation begins, alcohol throws off refractometer Brix readings, so this straight conversion no longer gives the true gravity, use the refractometer final-gravity tool for that. °Brix and °Plato are close enough to treat as the same for homebrewing.
Frequently asked questions
How do I convert Brix to specific gravity?
Use the standard formula SG = Brix ÷ (258.6 − (Brix ÷ 258.2 × 227.1)) + 1. For 12 °Brix that's about 1.048. The tool does it both ways instantly.
What is the difference between Brix and specific gravity?
Brix measures dissolved sugar as a percentage by weight; specific gravity measures the solution's density relative to water. Refractometers use Brix, hydrometers use gravity, both indicate how much sugar is present, just on different scales.
Is Brix the same as Plato?
Almost. Both measure sugar by weight percentage and are defined slightly differently, but for practical homebrewing the difference is negligible, a Brix reading and a Plato reading are effectively interchangeable.
Can I use this on fermenting beer?
No, once alcohol is present it distorts refractometer Brix readings, so a plain Brix-to-gravity conversion reads the final gravity too high. Use it for pre-fermentation wort or must; for post-fermentation refractometer readings, use the refractometer correction tool.
Why does my refractometer disagree with my hydrometer?
On unfermented wort they should match after this conversion (calibrate the refractometer with distilled water at zero). If they differ on fermenting beer, it's the alcohol skewing the refractometer, the hydrometer is right there.
How do I convert specific gravity back to Brix?
The reverse cubic works from the gravity: for example 1.048 comes out to about 12 °Brix, and 1.060 to about 14.7 °Brix. Enter the gravity in the SG field and the tool returns the Brix, useful when a recipe lists one scale but your instrument reads the other.
What Brix reading do I need for a target gravity?
Roughly divide the gravity points by four as a first guess: for a 1.055 target (55 points) aim for about 13.5-14 °Brix in your pre-boil or pre-pitch wort. Use the converter for the precise figure, since the quick rule drifts at higher gravities.