Please note that the result is an estimation based on normal conditions (68°F or 20°C). The actual voltage drop can vary and depends on the type (number of strands in wire) and the condition of the wire, the conduit being used, the temperature, the connectors, the frequency etc.
The input of negative values and zero "0" is not allowed. EXCEPT for the input of AWG wire sizes, where 0 (0 or 1/0), -1 (00 or 2/0), -2 (000 or 3/0), -3 (0000 or 4/0), -4 (00000 or 5/0) and -5 (000000 or 6/0) are accepted. "0" is also allowed for the resistivity [Ω·m].
In this case, values for AWG range from -5 (000000 or 6/0) to 40. Attention: Only integers will be accepted. All decimals will be truncated automatically! Thus, 3.3 or 3.9 will become 3.