GeoConvert is an open access geography matching and conversion tool for 2011, 2001 and 1991 census geographies. GeoConvert allows users to obtain and manipulate complex geographical and postcode data in a straightforward way. GeoConvert is freely available to all: GeoConvert Citation: Office for National Statistics, Postcode Directories (2015): GeoConvert. UK Data Service (Edition: November 2015). DOI: https://doi.org/10.5257/census/geoconvert-1 The main functions of the GeoConvert tool are to: • provide postcode metadata (deprivation scores, grid-reference co-ordinates, area classifications, etc.) • provide details of the geographical relationships (intersections/matches) between zones in different geographies • re-sample (convert) data from one geography to another