Geocoding Playground

Geocoding Playground is a browser-based geocoder that operates without the need for a backend server. It leverages DuckDB-WASM for efficient data querying and Overture Maps address data, providing access to over 469 million addresses. This open-source project allows users to perform geocoding operations directly within their web browser, making it a highly accessible and self-contained solution for address lookup and location services. Its architecture is designed for performance, utilizing HTTP range requests to query Parquet files directly.

The tool offers comprehensive forward geocoding, allowing searches by street, postcode, or full address across 39 countries. Additionally, it supports reverse geocoding, enabling users to find the nearest addresses by clicking on an interactive map or inputting coordinates. A key feature is its country-aware parsing, with dedicated address parsers for multiple regions including the US, Germany, France, and Japan, ensuring accurate and format-specific logic. Performance is enhanced through a three-tier caching system, which includes WASM initialization, country prefetch, and a tile LRU cache, resulting in sub-second query times.

Built as a pnpm monorepo, Geocoding Playground includes a pure TypeScript library (@walkthru-earth/geocoding-core) for its core functionalities. The interactive map is powered by MapLibre GL, featuring H3 tile overlays and result markers for clear visualization. Users can also switch between different Overture Maps releases and toggle between light and dark modes, adapting to system preferences. This project serves as a robust example of client-side geospatial data processing and visualization.