1. An image forming apparatus that includes recording heads, the recording heads ejecting recording liquids of a plurality of colors onto a recording medium, and performs multiple-color recording, the image forming apparatus comprising: a reference-patch forming unit configured to record a reference patch on the recording medium, the reference patch being formed by overlaying dot array patterns recorded with the recording liquids of different colors, the dot array patterns having no correlation therebetween; a detection-patch-group forming unit configured to record a detection patch group including detection patches on the recording medium, each of the detection patches being formed by overlaying dot array patterns recorded with the recording liquids of the different colors, the dot array patterns having a same cycle of regular dot array, the detection patches being allocated with different misregistration amounts of the dot array patterns; and a color-misregistration correcting unit configured to correct color misregistration based on results of comparison between color tone of the reference patch and color tone of each of the detection patches of the detection patch group, wherein the reference-patch forming unit and the detection-patch-group forming unit form the reference patch and the detection patch group, respectively, such that a color difference between the reference patch and a detection patch of the detection patches of the detection patch group, to which zero is allocated as the misregistration amount, is equal to or lower than 1.0 when the reference patch and the detection patch are recorded by using a combination of the recording medium and the recording liquids.