OpenStreetMap API
OpenStreetMap (openstreetmap.org) has 3 public methods: get coordinates for an address, search places and get address for coordinates. Each costs 1 credit per completed run (1¢ with pay as you go); failed runs are free.
Unofficial. Not affiliated with or endorsed by OpenStreetMap.
Methods
3Finds map coordinates and address details for an address or place on OpenStreetMap, optionally restricted to a country.
Returns coordinates, full address, place type, address parts, OpenStreetMap link, bounding box
Readopenstreetmap.org/get_coordinatesFinds named places or kinds of places in a city or area, in search order, using OpenStreetMap Nominatim. Results may be fewer than requested. Data © OpenStreetMap contributors (ODbL).
Returns name, type, full address, coordinates, OpenStreetMap link
Readopenstreetmap.org/search_placesTurns map coordinates into a readable address with OpenStreetMap Nominatim, at address, street or city detail, with the address parts and an OpenStreetMap link. Results reflect the nearest mapped feature.
Returns full address, place name, type, house number, road, neighbourhood, city, state or region, postcode, country, OpenStreetMap link
Readopenstreetmap.org/get_address