How do you find your body volume using a tape measure?

Answer 1

ACCURATELY measure a container into which your body will fit comfortably. Once you know the volume, fill the container with water.

Lower yourself into the water, allowing excess to spill over the top then climb out. By measuring the amount that the water that has spilled over you are effectively measuring your body volume. You can get a pretty accurate measurement by using the tape measure to see how much the water volume has dropped after you get out of the water.

depends what you mean by accuracy and to what degree. the theory of fractals says that with one measuring instrument you would read x units. with a second smaller measuring instrument to achieve greater accuracy you would read y units (y bigger than x). Moving to a third yet small measuring instrument you would read z units (z > y >x) and so forth. You can never get a truly accurate answer.

Failing all of that use Archimedes displacement principle and get a good estimate !

An alternative method of measuring body volume accurately is through the use of a 3D Body Volume Index (BVI) scanner. The BVI scanner is specifically designed to calculate risk factors associated with a person's shape, through analysis of weight and body fat distribution by body section and body volume measurement.