Brix to Specific Gravity Converter
The Brix-to-SG conversion uses the ICUMSA Method GS4-13 polynomial, which models the relationship between sucrose concentration by weight (Brix) and the resulting specific gravity...
Formula
Source: ICUMSA Method GS4-13 (2009); ASBC Methods of Analysis (Beer-2B); TTB Ruling 2012-2 | Last reviewed: July 3, 2026
Examples
12 brix
= 1.0484 SG
12°Bx — typical beer wort Original Gravity
20 brix
= 1.0833 SG
20°Bx — typical chardonnay grape must at harvest
25 brix
= 1.105 SG
25°Bx — typical cabernet sauvignon grape must
65 brix
= 1.3222 SG
65°Bx — corn syrup concentrate
Quick Reference Table
| Brix (°Bx) | Specific Gravity (SG) | Sugar (g/L) | Industry Application |
|---|---|---|---|
| 0 | 1 | 0 | Pure water reference |
| 5 | 1.0198 | 51.5 | Light beer / low-sugar beverage |
| 10 | 1.0401 | 104 | Standard beer wort |
| 12 | 1.0484 | 125.7 | Average beer Original Gravity |
| 15 | 1.0608 | 158.5 | Strong beer / Imperial styles |
| 18 | 1.0736 | 192.4 | Pommeau / cider base |
| 20 | 1.0833 | 215.2 | White wine (Chardonnay, Sauvignon Blanc) |
| 22 | 1.0929 | 238.6 | Late-harvest Riesling / rosé |
| 25 | 1.105 | 270 | Red wine (Cabernet, Syrah) |
| 28 | 1.1171 | 302 | Ice wine / high-Brix dessert wine |
| 40 | 1.1773 | 418.9 | Fruit juice concentrate |
| 50 | 1.2317 | 537.3 | Maple syrup base |
| 65 | 1.3222 | 720.4 | Corn syrup (HFCS-65) |
| 75 | 1.397 | 851.5 | Refined sugar syrup (high-Brix) |
Where is this used?
In winemaking, grape must typically ranges 18-28°Bx.
The target for harvesting white wine is 20-23°Bx, for red wine 23-26°Bx.
A Brix reading predicts final alcohol: ABV ≈ Brix × 0.55 - 0.5 for typical wine fermentation.
In brewing, original wort measures 10-15°Bx for most beer styles; final gravity is 2-5°Bx.
The apparent extract (OG - FG) multiplied by 131.25 gives approximate ABV.
In sugar refining, Brix of process juice streams is measured continuously with inline density meters, with values from 12-18°Bx in diffuser juice to 60-70°Bx in thick juice to 70-80°Bx in final massecuite.
Real-World Usage Scenarios
Winery Harvest Decision
A Napa Valley Cabernet Sauvignon vineyard in late September 2024 measures 24.2°Bx in the refractometer at the crush pad. The winemaker converts to SG: SG = 1 + (24.2 / (258.6 - (24.2/258.2 × 227.1))) = 1.1020. This corresponds to potential alcohol of approximately 24.2 × 0.55 - 0.5 = 12.8% ABV if fermented to dryness. The winemaker decides to harvest the next morning based on this and the refractometer-corrected pH (3.65) and TA (6.2 g/L).
Sugar Refining Process Control
At a Louisiana sugar refinery, the inline Brix analyzer in the evaporator train reads 56.4°Bx (SG 1.2733) for the thick juice leaving the third effect. The target for the next stage (vacuum pan seeding) is 70-72°Bx. The plant operator monitors the Brix and steam pressure to optimize the evaporation rate. A 0.5°Bx deviation from target corresponds to a 4-5% change in crystal yield, so maintaining Brix within ±0.2°Bx of setpoint is the daily operational goal.
Common Mistakes to Avoid
Confusing Plato and Brix readings
Plato and Brix are nearly identical (within 0.05° for typical wort), but Plato is calibrated to 17.5°C/63.5°F while Brix is calibrated to 20°C/68°F. A Plato reading of 12.4°P is not exactly 12.4°Bx — using them interchangeably in lab records leads to small inconsistencies that auditors and TTB inspectors notice.
Ignoring temperature correction
A refractometer reading of 12.0°Bx at 25°C is actually 12.4°Bx corrected to 20°C. A 5°C error in sample temperature produces a 0.4°Bx error, which translates to a 0.4% potential ABV error. Most refractometers have automatic temperature compensation (ATC) — verify it's enabled and calibrated to the right reference temperature (usually 20°C).
Using Brix scales for high-concentration solutions
The ICUMSA polynomial is calibrated for 0-30°Bx. Above 30°Bx (high-Brix juices, syrups, corn syrups), the polynomial diverges from true SG by up to 0.005 SG. For 60+°Bx industrial solutions, use a pycnometer or vibrating-tube density meter, not the Brix polynomial.
Industry Standards Referenced
Frequently Asked Questions
What is the exact formula for converting Brix to specific gravity?
Per ICUMSA Method GS4-13: SG ≈ 1 + (Bx / (258.6 - ((Bx / 258.2) × 227.1))). For 0-30°Bx, this is accurate to ±0.0001 SG units. The simpler approximation SG ≈ 1 + 0.00373·Bx + 0.0000012·Bx² matches within 0.0001 SG in the 0-20°Bx range. Reverse: Bx ≈ 258.6 × ((SG - 1) / (258.6 - 227.1 × (SG - 1))).
Is Brix the same as specific gravity?
No. Brix (°Bx) measures sucrose concentration by weight (1°Bx = 1% sucrose by mass), while specific gravity (SG) is the ratio of solution density to water density at the same temperature. 12°Bx = SG 1.0484, not 1.12. The conversion is non-linear because dissolved sucrose volume change is non-linear with concentration.
Why is Brix used in winemaking instead of specific gravity?
Brix is more directly meaningful for the winemaker: °Bx tells you the percentage of fermentable sugar in the must, predicting potential alcohol. In US winemaking, Brix is the legal measurement (per TTB Ruling 2012-2) for sugar determination.
How accurate is the Brix polynomial for non-sucrose solutions?
The polynomial is calibrated for pure sucrose. For fruit juices, honey, or other sugar mixtures, the relationship is approximate because dissolved solids include acids, salts, and other dissolved material. A 20°Bx apple juice measures SG 1.082-1.085, slightly different from the polynomial's 1.0833. Error is usually <0.5% for fresh fruit juices but can be 2-3% for high-acid solutions.
What is the temperature correction for Brix?
Per ICUMSA Method GS4-13 and TTB Ruling 2012-2, the standard reference temperature for Brix is 20°C (68°F). For each 1°C deviation, the Brix reading changes by approximately 0.06°Bx. Most modern refractometers have automatic temperature compensation (ATC) calibrated to 20°C. Hydrometer readings need manual correction using a published table.
Reviewed for accuracy
Cross-referenced against ICUMSA polynomial, ASBC standard methods, and Engineering Toolbox Brix table · Last reviewed: July 3, 2026
All calculations are for reference only. Always verify with manufacturer data and a qualified engineer for critical applications. Learn about our editorial process.