Centimeters and meters measure distance in the metric system. Cubic meters, however, measure volume. Volume represents the three-dimensional space an object takes up. Therefore, you need to have three measurements in centimeters or meters to convert to cubic meters. If you have one measurement in centimeters and you want to find the volume in cubic meters, convert the centimeters to meters and then measure the other dimensions in meters.
Convert the centimeter measurement to meters by dividing the number of centimeters by 100. For example, if a box's length equals 80 cm, divide 80 by 100 to get 0.8 meters.
Measure the other two dimensions of the object in meters. For example, if you have a box and you know the length is 0.8 meters, measure the width and height in meters.
Multiply the length in meters by the width in meters by the height in meters to calculate the volume in cubic meters. For this example, if the box is a cube, meaning all three dimensions are equal, multiply 0.8 meters by 0.8 meters by 0.8 meters to get 0.512 cubic meters.