Gwajin Gasar Fecal (wanda kuma aka sani da Gwajin Immunochemical na Fecal ko FIT) gwajin gwaji ne na likita da ake amfani da shi don gano ɓoyayyun jini a cikin samfuran stool. Kalmar “fakuwa” tana nufin ɓoyayye ko ɓoyayye, kuma “najasa” tana nufin najasa ko stool. Yawancin lokaci ana amfani da gwajin azaman kayan aikin tantancewa don ciwon daji na hanji da sauran cututtukan narkewa. Gwajin ya gano akwai jinin da ba za a iya gani da ido ba, don haka ake kiransa da “boko”. Gwajin ya ƙunshi tattara ƙaramin samfurin stool da yin nazari akan kasancewar jini ta hanyar amfani da sinadarai. Idan an gano jini, ana iya buƙatar ƙarin gwajin bincike don sanin dalilin.