Relationships between the size of otoliths and vertebrae, and body length are presented for eleven teleost species of the north-east Atlantic. Relationships between teleost size and weight are also presented for these species. These equations can be used to reconstruct the original dimensions of prey from the size of hard structures found in food samples of marine piscivores. For each fish species we selected otoliths and vertebrae which possessed unique features enabling diagnosis of specimens to the level of genus or species. Linear and non-linear functions provided the best fit for relations between hard structure size and fish length, and exponential functions yielded the best predictors for fish weight. For some species, the relationships obtained in this study differed from similar functions obtained by other authors at different locations. This calls for caution when using equations derived from specimens on other locations, especially if precise quantitative data are required.