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An attempt was made to collect all published species comparisons of overall digestive capacity of goats with sheep, cattle and buffalo. Statistical analyses were carried out on all data sets resulting from in vivo estimates based on total faecal collection and on part of these data sets classified as category I. Excluded from category I were data sets from papers in which species and diet effects were confounded, in which proper handling of orts (if any) was not evident, and/or which showed clear inconsistencies in the presented results. From 92 sources, 342, 45 and 9 (218, 34 and 1 category I) data sets comparing overall feed digestibility (i.e., of organic matter, dry matter, energy or total nutrients) in goats with sheep, cattle and buffalo, respectively, were collected. In category I data sets, overall feed digestibility was significantly higher in goats compared with sheep but the difference was very small (+0.8 percentage units). The difference was not significantly affected by species-average digestibility or crude fibre content but was increased at low crude protein content in the diet. In category I data sets, overall feed digestibility was significantly lower in goats compared with cattle (−2.7 percentage units). The difference was not significantly affected by species-average digestibility or crude fibre content but increased with decreasing crude protein content of the diet. It is concluded that the slightly higher overall feed digestibility in goats compared with sheep is of no practical significance with the possible exception of diets very low in crude protein content. On the other hand, overall feed digestibility is lower in goats compared to cattle and the difference tends to be larger in low protein diets.