InfoPlease lists some common weight and measurement conversions, such as 1 pound equals 0.45 kilograms, and one meter is equivalent to 39.37 inches. The list of conversions covers length, area, weight, volume and capacity.
The conversions on InfoPlease are precise, such as 1 square kilometer equals 0.386 square miles, and 1 U.S. quart equals 0.946 liter. This website also makes the distinction between U.S. gallons and British imperial gallons, pointing out that one imperial gallon equals 1.2 U.S. gallons or 4.5 liters.
PetEducation.com provides a clear and easy-to-read chart showing common weight and measurement conversions. There is also a list of unit conversion factors for weight. For example, to convert ounces to grams, multiply by 28.35.
When precision is not as important, rounding the numbers makes conversion simpler. For example, 2 pounds is about 1 kilogram, and 1inch is about 2.5 centimeters. Eight kilometers is about 5 miles, and 1 liter is close to 1 quart.