A level converter includes a cross-coupled section for holding data and a first switching section connected in series with the cross-coupled section and supplied with a differential input signal. The level converter has a second switching section, a current mirror connection section, a third switching section, and an input/output matching evaluation section. The second switching section is connected in parallel with the cross-coupled section, and the current mirror connection section is connected in a current-mirror configuration with a transistor in the second switching section. The third switching section is connected in series with the current mirror connection section, and the input/output matching evaluation section is used to control a transistor in the third switching section by receiving the input signal and an output node signal.