Atmosculator also provides the option of calculating properties under non-standard conditions - i.e. when the temperature differs from that of the standard model.
Although the values provided by Atmosculator have been carefully checked against the original U.S. Government source, their accuracy cannot be guaranteed, so please use this tool at your own risk.
Atmosculator includes extensive Help on the basis of the model and a mathematical derivation showing how the properties are calculated. For your online convenince, this description of the Standard Atmosphere Model is reproduced here.