Electoral system for the president

Afghanistan, Election Law (Official Gazette, Issue No 1226, 25 September 2016) [English translation], accessed 28 October 2018

Article 45: (1) The President shall be elected by obtaining more than 50% of the votes of voters through free, general, secret and direct polling.

(2) In case none of the candidates receive the majority of more than 50 per cent of the votes in the first round, the second round election is held within 2 weeks after the date of announcement of final election results, and in this round only the two candidates participate who have received the highest votes during the first round. […]