What is the output of an XOR gate if both inputs are the same?

The output of an XOR (exclusive OR) gate is true or high (1) only when the inputs are different. When both inputs are the same, whether they are both true (1) or both false (0), the output will be false or low (0).

To further clarify, an XOR gate is designed to output a high signal only when exactly one of the two inputs is high; when both are the same, the condition for outputting a high signal is not met, thus resulting in a low output. In essence, the XOR gate acts as a check for disparity between the two inputs, and when that check fails (when the inputs are identical), the output is conclusively low.