How Many Gallons in a Kilogram?

Divide the kilograms by what one gallon of the ingredient weighs in kilograms. For water, the divisor is the one in the formula above. By USDA figures, a US gallon of all-purpose flour weighs about 2 kilograms and a gallon of granulated sugar about 3.2 kilograms.

Say you buy a 10 kg sack of flour. It needs 10 ÷ 2 = 5 gallons of storage space. The same weight of sugar needs only about 3.13 gallons.

This is the reverse of the gallons to kilograms conversion. Use whichever direction starts from the number you already have.

The imperial gallon is about a fifth larger than the US one, so the same kilograms fill fewer imperial gallons. A kilogram of water is 0.22 of an imperial gallon, compared with the US figure above.

Check which gallon a tank, drum or bucket is rated in before you fill it. A 5 imp gal drum, for example, holds about 6 gal in US measure.

The heavier a food is for its size, the fewer gallons a kilogram of it needs. Liquids such as water and milk are compact, so 10 kg of whole milk fills only about 2.56 US gallons.

Powdered sugar sits at the other end. 10 kg of it takes up about 5.21 gallons, about twice the space of the same weight of milk. A storage plan based on water would leave half of that sugar without a home.

If your storage buckets are rated in gallons, a quick sum tells you how many to buy. A 5 gal bucket holds about 10 kilograms of all-purpose flour or 16 kilograms of granulated sugar.

A 25 kg sack of flour needs about 12.5 gallons, so plan on three such buckets rather than two and a half. Leave a little headroom so the lid seals, and expect settled flour to take slightly less room than freshly poured flour.