MapTiler is a graphical application that allows users to easily publish maps online by georeferencing scanned maps and transforming coordinate systems. It can generate tiles following the TMS and WMTS standards to be displayed in a simple web viewer using APIs like OpenLayers or Google Maps. National libraries and government agencies in several countries are among the users of MapTiler. The program is available for free download and its development has been supported by Google, the National Library of Scotland, and other organizations.