By the time Tanjiro puts a fight to the spider demon twelve demon moon with the help of his sister (finally defeated by Giyu Tomioka) , Tanjiro already defeated an ex twelve demon moon. Later in the manga is revealed that,
They are in kanoe rank. But it's never shown when they got the ranks inbetween
Is there an official guide, audiobook, interview or something which shows how they demon slayers increased ranks? Which rank is Tanjiro by the time he fights the spider demon twelve demon moon?