An image forming apparatus includes: a sheet feeding conveyor that feeds and conveys a recording medium to a conveyance path; an image former that performs image formation on the recording medium; a medium sensor that is disposed on an upstream side of the recording medium from the image former on the conveyance path and measures one or more sheet physical properties regarding the recording medium conveyed; a first hardware processor that determines a type of the recording medium on a basis of the sheet physical properties measured by the medium sensor; a second hardware processor that determines conveyance performance for the recording medium; and a third hardware processor that determines whether or not to perform the image formation on a basis of the conveyance performance in a case where the type of the recording medium determined by the first hardware processor is a type out of product specifications.