The continuous production of carbon monoxide (CO) and hydrogen (H) by dry reforming of methane (CH) is demonstrated isothermally using a ceramic redox membrane in absence of additional catalysts. The reactor technology realizes the continuous splitting of CO to CO on the inner side of a tubular membrane and the partial oxidation of CH with the lattice oxygen to form syngas on the outer side. LaSrCoFeO (LSCF) membranes evaluated at 840-1030 °C yielded up to 1.27 μmol    s from CO, 3.77 μmol g s from CH , and CO from CH at approximately the same rate as CO from CO. We compute the free energy of the oxygen vacancy formation for LaSrBB'O (B, B'=Mn, Fe, Co, Cu) using electronic structure theory to understand how CO reduction limits dry reforming of methane using LSCF and to show how the CO conversion can be increased by using advanced redox materials such as LaSrMnO and LaSrMnCoO .