We present a vector map of the limits of oceans and seas intended to be integrated into a geographic information system (GIS). This map is based on the document S-23 titled “Limits of Oceans and Seas” and published by the International Hydrographic Organization (IHO). The third edition of this document, published in 1953, still serves as an official reference. The realization of this map from a text containing numerous ambiguities, disused place-names, or imprecise coordinates required important documentary investigations. This was made possible through the use of online resources such as map libraries, satellite imageries, geographic names databases, and institutional geoportals. The main innovations of our map are its accuracy, its precision of about 10 s of meridian arc, and its consistency with the Global, Self-consistent, Hierarchical, High-resolution Shoreline database and with satellite images such as Land Satellite and moderate-resolution imaging spectroradiometer. All remaining uncertainties for the drawing of limits are presented in the results. Although based on an IHO document, our map does not possess any official status. Nevertheless, we hope that our map will facilitate and encourage more detailed spatial analyses related to oceans and seas. This map is freely available for noncommercial use.