A developing unit includes a developer carrying member, a supplying compartment, a recovery compartment, and an agitation compartment. The developer carrying member develops a latent image formed on an image carrier with a two-component developer. The supplying compartment has a developer supplying transporter to supply the two-component developer to the developer carrying member while transporting the two-component developer. The recovery compartment has a developer recovery transporter to transport the two-component developer recovered from the developer carrying member. The agitation compartment has a developer agitation transporter to agitatingly transports developer. The developer agitation transporter includes a first screw having a screw pitch to transport developer to an upstream end of the supplying compartment from a downstream end of the agitation compartment. The developer supplying transporter includes a second screw having a given screw pitch, which is greater than a screw pitch of the first screw.