Topofacile is a free geographic-data service developed by Yann Lijour to make high-quality French topographic information easier to access. Designed for architects, engineers, and planning and design consultancies, it lets users select an area in France and generate downloadable 2D and 3D files using data that includes high-precision IGN information.

Available layers cover topography and contour lines, buildings, roads and railways, cadastral parcels, rivers and other water features, vegetation, and green spaces. Users can also consult satellite imagery and historical maps, including Cassini, military survey, 1950s, and IGN sources. Output formats include DXF for tools such as AutoCAD and SketchUp, and JSON for structured geographic data; SVG is also offered for 2D files. The service supports Lambert 93 and WGS84 projections and provides options for adjusting parameters such as contour intervals and building details. Additional map-based features include terrain profiles, solar-shadow calculations, and visibility-range analysis. Topofacile is maintained with human and technical resources and invites users who value the service to support its continued development through donations.