Patent attributes
An image forming apparatus includes a medium storing part storing mediums, a sheet feeding part feeding the medium from the medium storing part, an image forming part forming an image to the medium, a residual quantity detecting part, a storage part, and a residual medium estimating part. The residual quantity detecting part detects a residual quantity of the mediums stored in the medium storing part as a relative residual quantity with regard to a maximum storing quantity of the mediums in the medium storing part. The storage part stores maximum storing number of the mediums corresponding to the maximum storing quantity of the medium storing part. The residual medium estimating part calculates number of estimated residuals of the mediums stored in the medium storing part on the basis of the relative residual quantity detected by the residual quantity detecting part and the maximum storing number stored in the storage part.