Data sources and terms

What MapNC uses, who to credit, and what you may do with what it makes. Not legal advice.

Using MapNC

© 2026 Winston Moy. All rights reserved. Free to use as a web app, personal or commercial. The files MapNC produces (heightmaps, route layers, SVG, DXF, STL) are yours to use however you like, subject to the data credits below. Copying, modifying, redistributing or hosting MapNC's code needs written permission.

MapNC's own code is covered by that. The libraries it ships keep their own licences: Leaflet (BSD-2-Clause), geotiff.js (MIT) and Delaunator (ISC). Elevation data and map tiles are subject to their providers' terms, below.

Elevation data

USGS 3D Elevation Program (3DEP), via The National Map. Courtesy of the U.S. Geological Survey. U.S. Government work, public domain; please credit USGS.
NRCan High Resolution Digital Elevation Model, from the Canada Centre for Mapping and Earth Observation. Contains information licensed under the Open Government Licence – Canada.
NOAA NCEI global bathymetry mosaic (optional sea floor depths when Level the sea is on). Courtesy of the NOAA National Centers for Environmental Information. U.S. Government work, public domain; please credit NOAA NCEI. The mosaic is compiled from several bathymetry sources, so check the NCEI bathymetry page before redistributing derived data.
AWS Terrain Tiles (Terrarium format), from the Registry of Open Data on AWS. The tiles combine several public datasets, including SRTM, USGS NED/3DEP, GMTED2010, ETOPO1, ArcticDEM, NRCan CDEM, EU-DEM and GEBCO bathymetry, among others. The full list and licence terms are in the Tilezen attribution notes; please check them before redistributing derived data.

Borders

Optional country and state or province borders in the SVG and DXF export come from Natural Earth and, for US state lines and the US / Canada border along the 49th parallel, the US Census Bureau cartographic boundary files. Both are public domain. The lines are generalised: US state lines and some straight country borders are within about 250 m of the real line, the rest can sit up to about a kilometre off. They ship with MapNC; nothing is fetched from another site.

Background maps

Shown on the map for display only. None of it is used in the heightmap.

Satellite: Esri World Imagery. Tiles © Esri, Maxar, Earthstar Geographics, and the GIS User Community, subject to Esri's terms.
USGS Topo: tiles courtesy of the U.S. Geological Survey (US only).

Privacy

MapNC runs in your browser. Your route files and the elevation data are processed on your device and are not uploaded to MapNC. Our servers keep ordinary request logs (such as your IP address, the time and the page requested), as any website does. If you use the Send feedback form, the message you write (and your contact details and browser version, if you include them) is sent to the project owner, and nothing is sent until you press Send. The data providers and map services listed above receive the requests your browser makes to them, such as the area you are looking at, and so can see your IP address too.

Sample route

A recording of a hike to the Sierra Buttes Fire Lookout, supplied by the project owner. Timestamps and sensor data were removed; only positions and elevation remain.