Sugar syrup by weight
Simple syrup is just sugar dissolved in water, but the proportion changes everything: sweetness, thickness, shelf life and how much water it adds to a drink. Bartenders, pastry cooks and beekeepers all use sugar syrups, and the most precise way to describe them is by degrees Brix (°Bx), the grams of sugar in 100 grams of syrup.
The calculation
To reach a target Brix B with a given weight of water W:
Sugar = W × B ÷ (100 − B)
The calculator also estimates the syrup’s specific gravity from the Brix and gives its volume and its strength in degrees Baumé (°Bé), a scale still used in pastry and candy making.
Worked example
1 cup of water (about 237 g) made into a 50 °Brix syrup (1:1 by weight):
| Result | Value |
|---|---|
| Sugar to dissolve | 237 g |
| In cups of granulated sugar | 1.18 cups |
| Weight of syrup | 473 g |
| Volume of syrup | about 1.62 cups |
| Specific gravity | 1.233 |
| Baumé | 27.4 °Bé |
Notice that the syrup’s volume is less than the sum of the water and sugar volumes, because sugar dissolves into the spaces between water molecules.
By weight or by volume?
Many recipes say “1 cup sugar, 1 cup water”, which is about 200 g of sugar in 237 g of water, or 46 °Brix. That is slightly thinner than a true 1:1 by weight. For cocktails, the difference is small, but measuring by weight gives consistent results.
Common syrups
| Syrup | Ratio (sugar:water by weight) | Brix |
|---|---|---|
| Light syrup for canning fruit | about 1:3 | 25 |
| Simple syrup | 1:1 | 50 |
| Pastry soaking syrup (30 °Bé) | about 1.35:1 | 57 |
| Rich simple syrup | 2:1 | 67 |
| Bee feeding syrup (fall) | 2:1 | 67 |
Making it
Heat the water, add the sugar and stir until fully dissolved; it does not need to boil. Rich syrups dissolve more easily warm. Let the syrup cool before bottling and keep it refrigerated.
Shelf life
Sugar ties up water, so microbes find it hard to grow in concentrated syrups. A 1:1 syrup keeps about a month in the refrigerator; a 2:1 rich syrup keeps several months. A spoonful of vodka can extend the life of a lighter syrup. Discard any syrup that becomes cloudy or smells off.