An inkjet recording apparatus includes: a head having a plurality of nozzles for ejecting ink onto a recording medium; a conveyance device which conveys the recording medium in a prescribed direction along a conveyance path; an investigation pattern generation device which generates a thinned-out investigation pattern that is to be output by causing the nozzles other than a portion of the plurality of nozzles of the head to eject the ink; a reading device which is provided on the conveyance path and which reads in the investigation pattern output onto the recording medium; and a checking device which performs comparison between data of the investigation pattern read in by the reading device and data of the investigation pattern generated by the investigation pattern generation device, wherein a determination rate of ejection failure nozzles is found from result obtained by outputting the investigation pattern generated by the investigation pattern generation device onto the recording medium from the head, reading in the output investigation pattern by the reading device, and performing the comparison between the data of the investigation pattern thus read in and the data of the investigation pattern generated by the investigation pattern generation device.