Inverse diffusion flame (IDF) configurations have shown to be robust to changes in fuel feed and combining desired characteristics of both diffusion and premixed flames. In this work, methane IDFs are characterized in a multi-slit burner. To this end, a multi-technique experiment with photography, particle image velocimetry, and flame chemiluminescence through spectroscopy is conducted. The flames studied encompass a range of conditions (0 ≤ Vr ≤ 100) with laminar flow at two different power outputs (238 and 476 W). Four characteristic IDF structures were identified and denominated as types A, B, C, and D. Type A do not exhibit IDF-like characteristics and behave like normal diffusion flames. Types B, C, and D were found to exhibit a dual nature, with regions varying from a diffusion-like regime to a premixed-like regime. The velocity ratio Vr was found to be the most important parameter when characterizing IDF, whereas the use of a global equivalence ratio ϕg can be misleading because it does not offer insight in actual reaction stoichiometry. Type C flames displayed ideal characteristics for the application in appliances as a result of its stability and absence of undesired yellow tips.