Depends a lot on the area you are working in, most European countries have open access soil data at high resolution, but elsewhere it varies a lot.
FAO data has a global coverage, but it is coarser resolution: http://www.fao.org/soils-portal/soil-survey/soil-maps-and-databases/harmonized-world-soil-database-v12/en/
Corine land cover data might also be useful for inferring soils: https://www.eea.europa.eu/publications/COR0-landcover