Data Sources
This page documents the geographic data sources used by SizeOnMap.com, the licensing terms that apply, and the limitations you should be aware of when interpreting the maps.
What we use: Base map tiles and underlying global geography.
Source: OpenStreetMap.org
License: Open Database License (ODbL)
Notes:
- Data is created and maintained by a community of contributors worldwide.
- Accuracy depends on local coverage; some regions are more detailed than others.
- Boundaries may include disputed claims or vary from official government definitions.
What we use: Country-level (ADM0) and first-level administrative boundaries (ADM1).
Source: geoBoundaries
License: Creative Commons Attribution 4.0
Notes:
- Boundaries are compiled from official government data and other open sources.
- Updates may lag behind recent political changes.
- Boundaries in disputed areas may not align with every official position.
What we use: Polygon outlines of continents, used to provide large-scale context.
Source: Esri World Continents dataset
License: Esri Open Data, attribution required.
Notes:
- Dataset is generalized and not suitable for high-precision analysis.
- Shapes are intended for educational visualization, not for legal or scientific use.
What we use: Tool for simplifying and optimizing geographic datasets before serving them on the web.
Source: mapshaper.org
License: MPL 2.0
Notes:
- We use Mapshaper to reduce file size of boundary datasets while preserving recognizable shapes.
- Simplification may remove fine-grained details, so borders may appear less precise.
- Mapshaper does not provide original data; it processes the other datasets listed here.
- All maps are based on projections that distort either area, shape, or distance.
- SizeOnMap.com uses a consistent projection to allow comparisons, but distortion cannot be fully eliminated.
- Boundaries, coastlines, and territories may be subject to disputes and do not represent any political stance.
- This site is for educational and illustrative purposes only, not for navigation, planning, or legal uses.