Volume Converter — Liters, Gallons, Milliliters, Cups & More

Depends which gallon. US gallon = 3.785 liters. UK gallon = 4.546 liters. When a US recipe or fuel economy figure says "gallon," it means the smaller US one. When a British source says "mpg," it's the larger UK gallon — which is why UK mpg figures look better than US mpg for the same car.

1 US cup = 236.6 ml. Most people round this to 240 ml for cooking and it works fine. A metric cup (used in Australia and a few other places) is 250 ml. When in doubt, use the US cup definition unless the recipe is explicitly Australian.

Multiply fluid ounces by 29.57. So 8 fl oz = 237 ml (a standard cup), 12 fl oz = 355 ml (a can of soda), 16 fl oz = 473 ml (a pint glass in the US).

1 tablespoon = ~15 ml. 1 teaspoon = ~5 ml. These round numbers are standard in metric cooking — the official US values are 14.79 ml and 4.93 ml respectively, but the 15/5 convention is used by basically everyone.

Yes. Work out the volume in cubic meters or liters (length × width × depth in meters = m³, then ×1000 for liters), then convert to gallons if needed for US-sourced chemical dosing instructions. An average backyard pool is roughly 50,000–75,000 liters (13,000–20,000 US gallons).

1 cubic meter = 1,000 liters exactly. This is a clean metric relationship — a cube 1 meter on each side holds exactly 1,000 liters of water. It's also 1 tonne of water, which is a useful fact for engineering.

Divide 235.21 by the mpg figure. So 30 mpg ≈ 7.84 L/100km, 40 mpg ≈ 5.88 L/100km. For UK mpg, divide 282.48 by the mpg figure instead. L/100km is lower = more efficient; mpg is higher = more efficient.