A page buffer includes a first precharge circuit, a second precharge circuit, and a sense amplifying circuit. The first precharge circuit includes a first path for precharging a bitline connected to a nonvolatile memory cell. The second precharge circuit includes a second path for precharging a sensing node connected to the bitline. The second path is electrically separated from the first path. The sensing node is used to detect a state of the nonvolatile memory cell. The sense amplifying circuit is connected to the sensing node and the second precharge circuit, and stores state information representing the state of the nonvolatile memory cell. The second precharge circuit is configured to perform a first precharge operation for the sensing node and configured to selectively perform a second precharge operation for the sensing node based on the state of the nonvolatile memory cell after the first precharge operation.