Carnivores, particularly felids, face threats in many regions of the world. They are a crucial component of biodiversity with a functional role in the top of the food chain. Therefore, they have been the target of surveys and monitoring and ecological studies, most of which are based on footprint identifications, an efficient and low-cost method compared to other approaches. In these cases, species identifications may suffer from a high degree of bias due to the overlap in the size and shape of footprints among species. We experimented with small to medium captive wild felids of five species: ocelot, Leopardus pardalis, margay L. wiedii, oncilla, L. guttulus, domestic cat, Felis catus, and jaguarondi, Puma yagouaroundi).We tested for differences in footprint measurements, including main pad and toe pad sizes. We used humid sand as substrate and took measurements from several front and hind footprints of seven animals per species (except jaguarondi, for which only four animals were available). Our results showed that ocelot is the only species for which it is possible to obtain 100%-accurate footprint identifications, mainly because of its footprint area (i.e., length x width). The remaining species presented a wide variation in measurements, making them almost impossible to distinguish based solely on footprint dimensions. Our results suggest that researchers should restrict identification to the genus level or adopt a multidisciplinary sampling strategy by combining footprint detection with camera-trapping, visual observation, scat collection, molecular ecology techniques, and/or face-to-face interviews with local residents.