Objective:The paper aims to show how insertion gain responses can be translated into equivalent headphone responses, and vice versa.Design:The relationship between the response types is theoretically derived by allowing for real ear to coupler differences and for real ear unaided responses.Results:The necessary corrections for each of these factors are obtained from published data, and the combined correction factors are compared with independently obtained published data.Conclusions:The equations and data presented can be used to translate insertion gain responses into responses suitable for use with equipment using headphones and, by inference, insert phones.