A scan driver may include a first stage, a second stage, and a third stage. The first stage may include a first output transistor. The first output transistor may have a first buffer value. The second stage may be electrically connected to the first output transistor and may include a second output transistor. The second output transistor may have a second buffer value. The third stage may be electrically connected to the second output transistor and may include a third output transistor. The third output transistor may have a third buffer value. At least one of the second buffer value and the third buffer value may be unequal to the first buffer value.