**Forty kilograms equal approximately 88 pounds.** There are online tools that aid with metric to US customary unit conversions as well as an equation for manual calculations.

A kilogram (kg) is a unit of measurement in the International System of Units (SI) and is one of the terms used to describe weight. It is a metric standard that was developed in 18th century France. The weight of a kilogram is approximately the same as the mass of a liter of water. However, an object said to weigh a kg is defined as having a mass equal to the International Prototype of the Kilogram (IPK), which is a block of platinum-iridium alloy manufactured in France in 1889. A kg is the only SI unit with a physical object as its defining property.

The United States customary unit of measurement is developed from the English imperial unit. The US customary unit that would be similar to kg is the pound (lb). Converting kgs to lbs can be accomplished by using an online conversion chart or calculator. The conversion chart offers columns and rows that allow the user to find the desired measurement. Online conversion calculators like the kg-to-lbs converter allow the user to input the kg value and it automatically provides the lb. To manually convert kg to lb, multiply the kg value by 2.2046.