A memory device can dynamically select a voltage step size for programming (i.e., charging) memory cells. The memory device can increase the voltage step size to reduce programming time or decrease the voltage step size to reduce errors. The memory device can identify device conditions, such as temperature or amount of use (e.g., a count of program/erase cycles). The memory device can increase the voltage step size when the device conditions are less likely to cause errors (e.g., in a middle temperature range or below a threshold number of program/erase cycles) or can decrease the voltage step size when the device conditions are more likely to cause errors (e.g., in a high or low temperature range or above a threshold number of program/erase cycles).