A splitter includes a common transmission line, a first transmission line, a second transmission line, a third transmission line, a fourth transmission line, a resistor, and a first reactance circuit. The common transmission line is coupled between a common port and a common node. The first transmission line is coupled between a first port and a first node. The second transmission line is coupled between a second port and a second node. The third transmission line is coupled between the common node and the first node. The fourth transmission line is coupled between the common node and the second node. The resistor is coupled between the first node and the second node. The first reactance circuit is coupled between the first node and the second node. The first reactance circuit includes a first inductor and a first capacitor coupled in parallel, but it does not include any resistor.