Download websites that use OpenLayers

A map on a page is a commercial decision before it is a technical one. Sites that only need to show an address use whatever their CMS bundles and never think about it again. Sites that reach for OpenLayers are normally doing something harder and have someone on hand who can build it.

OpenLayers is a JavaScript mapping library published under the BSD licence and in continuous development since 2006. The library draws raster and vector tiles from many different sources, handles coordinate systems and projections properly rather than assuming one global scheme, and exposes control over rendering and interaction that hosted map widgets deliberately hide. Requirements of that kind cluster in planning portals, utilities, environmental monitoring, cadastral and land registry viewers, transport operators, universities and research groups.

Presence of OpenLayers is therefore a reasonable proxy for an in-house or contracted development team and for a project with genuine geospatial requirements. The licence matters as much as the capability. A permissively licensed library carries no per-view billing and no vendor account, which is why it appears so often in public sector and academic work where a metered commercial mapping API is awkward to procure and awkward to budget for over the life of a system.

For a researcher the interesting question is rarely whether one site uses the library. The questions worth a dataset are which sectors and which national domains have standardised on open mapping stacks, which organisations pair OpenLayers with a particular tile server, CMS or backend, and how that population compares with sites built on commercial map platforms. As of October 2026 we record OpenLayers on 11,620 sites, which is enough to segment by country, by domain suffix and by the rest of a site's stack rather than merely to state a total.

Undercounting is the honest caveat. OpenLayers ships as a module that is normally bundled and minified together with the rest of an application, and once identifiers are mangled and files are concatenated there may be nothing distinctive left to match. Detection works best where the library is loaded as a recognisable file or leaves its own class names and DOM structure intact. The visible population therefore skews toward simpler integrations and older pages, and the real installed base is larger than any figure we can defend.