He was born in Frankfurt am Main. He received his earliest training from his father, the painter Johann Georg Pforr (1745–98), and his uncle, the art professor and first inspector of the painting gallery in Kassel, Johann Heinrich Tischbein the younger (1742–1808). While studying at the Vienna academy, Pforr moved in 1810 to Rome in company of other students, including Johann Friedrich Overbeck, Ludwig Vogel and Johann Konrad Hottinger. Looking for lost spirituality in their art, they lived at the abandoned monastery of San Isidoro.
Pforr didn't have the chance to live long enough to see his art acknowledged. He died of tuberculosis in Albano Laziale, Rome at age 24.