Sashe na Zinariya, wanda kuma aka sani da Ratio na Zinariya ko Phi, yana nufin ra'ayi na lissafi wanda ke bayyana alaƙar da ke tsakanin adadi guda biyu wanda rabon ƙarami zuwa mafi girma ya yi daidai da rabon mafi girma jimlar duka biyun yawa. Wannan rabo yana kusan daidai da 1.6180339887 kuma galibi ana ɗaukarsa kyakkyawa da jituwa, kuma an yi amfani dashi cikin fasaha, gine-gine, da ƙira tsawon ƙarni. A cikin lissafi kuma, ana wakilta shi da harafin Helenanci phi (Φ).