The article introduces tinyworldmap, a world map designed for offline-first and low-bandwidth web apps, which is only 450 kB gzipped and supports all zoom levels. It can be used as a base map or as an offline fallback for OpenStreetMap tiles. The map displays the 10,000 most populous cities added to OpenStreetMap and has been optimized for client-side rendering on low-end devices. The project also provides a service worker to enable offline functionality for web apps with maps.