Gallons to Grams Conversion
Use this tool for the gallons-to-grams conversion of water, milk, or any other substance.
1 gal of…
| Substance | Density | 1 gal weighs / measures |
|---|---|---|
| Water | 1 g/ml | 3,785.41 g |
| Milk (whole) | 1.03 g/ml | 3,898.97 g |
| Flour (all-purpose) | 0.529 g/ml | 2,002.48 g |
| Sugar (granulated) | 0.845 g/ml | 3,198.67 g |
| Butter | 0.911 g/ml | 3,448.51 g |
| Vegetable oil | 0.92 g/ml | 3,482.58 g |
| Honey | 1.42 g/ml | 5,375.28 g |
| Table salt | 1.217 g/ml | 4,606.85 g |
| Rice (uncooked) | 0.85 g/ml | 3,217.6 g |
Why gallon (US) to gram needs a substance
Gallon (US)s measure volume and grams measure weight, so there is no single conversion factor between them. What bridges the two is density — how much a given volume of that particular substance weighs:
mass = volume × density
Water is the easy case: it is almost exactly 1 g/ml, so 1 ml of water weighs 1 g and the numbers look identical. Nothing else behaves that way — flour is about half as dense, and honey is nearly half again as dense.
Using this for recipes
Pick the ingredient from the list and the conversion uses a typical density for it. Dry ingredients are the least predictable: scooping flour straight from the bag can pack in 20% more than spooning it in gently, which is exactly why baking recipes prefer weights. If you have a density from a supplier or a label, choose Custom density and enter it.
Densities here are typical values for guidance. For anything where precision matters, weigh it.