The inductance calculated in this tool is the self-inductance, which is used in some simulations as just a portion of the total loop inductance. In this tool, the required variables are length and wire diameter. Note that there is no reference to the return path in this inductance estimator. When calculating the loop inductance, the self-inductance is taken into account as well as the mutual inductance of the return path and the self-inductance of the return path.