Abstract: An information processing apparatus includes a system device; a controller; a battery; a converter configured to convert an input voltage into an intermediate voltage at a predetermined voltage ratio, the input voltage is a voltage of input power from a power adapter; and a power feeder. The power feeder is configured to supply part or all of intermediate power that is power supplied from the converter, to the system device as system supply power; and charge the battery with part of the intermediate power left unsupplied to the system device, as charging power. The controller is configured to monitor a charging voltage and the system supply power, the charging voltage is a voltage of the charging power; and determine the input voltage based on the charging voltage and the system supply power.