An inkjet apparatus includes a plurality of heads to discharge droplets from a plurality of nozzles of the plurality of heads to form an image on a medium, a head driver to generate a drive waveform to discharge the droplets from the plurality of nozzles of the plurality of heads, a scanner to read a specific pattern from the image on the medium formed by the droplets discharged from the plurality of nozzles of the plurality of heads, and a discharge amount adjuster to correct the drive waveform to reduce differences in discharge amount of the droplets between the plurality of heads according to the specific pattern read by the scanner.