An image forming apparatus includes a controller configured to, each time a development roller of a developing device rotates by a particular rotational amount, increment a counter value stored in a storage, calculate a remaining amount of developer in the developing device, when the counter value is less than a first value, setting a remaining amount threshold to a first threshold, whereas, when the counter value is equal to or more than a second value, setting the remaining amount threshold to a second threshold, the second value being equal to or more than the first value, the second threshold being less than the first threshold, and when the calculated remaining amount is less than the set remaining amount threshold, control a transporter to transport developer stored in a developer box to the developing device.