We predicted the maps of soil organic carbon (SOC) and related soil properties in whole Japanese forest with a 10 m spatial resolution. The maps are outputs for the scientific paper entitled: “National-scale 3D mapping of soil organic carbon in Japanese forest considering microtopography and tephra deposition” (doi: 10.1016/j.geoderma.2021.115534). The dataset consists 4 soil properties (SOC concentration, SOC stock, bulk density and apparent coarse (rock) fraction) for 3 standard depth (0-5, 5-15 and 15-30 cm). The file information is as follows. OC_0_5_int.tif: SOC concertation in g/kg for 0-5 cm. OC_5_15_int.tif: SOC concertation in g/kg for 5-15 cm. OC_15_30_int.tif: SOC concertation in g/kg for 15-30 cm. BD_0_5_int.tif: Bulk density for 0-5 cm. To convert to Mg/m3 multiply by 0.01. BD_5_15_int.tif: Bulk density for 5-15 cm. To convert to Mg/m3 multiply by 0.01. BD_15_30_int.tif: Bulk density for 15-30 cm. To convert to Mg/m3 multiply by 0.01. CF_0_5_int.tif: Coarse fraction in % for 0-5 cm. CF_5_15_int.tif: Coarse fraction in % for 5-15 cm. CF_15_30_int.tif: Coarse fraction in % for 15-30 cm. OCS_0_5_int.tif: SOC stock in t/ha for 0-5 cm. To convert to kg/m2 multiply by 0.1. OCS _5_15_int.tif: SOC stock in t/ha for 5-15 cm. To convert to kg/m2 multiply by 0.1. OCS _15_30_int.tif: SOC stock in t/ha for 15-30 cm. To convert to kg/m2 multiply by 0.1. OCS 30_int.tif: SOC stock in t/ha for 0-30 cm. To convert to kg/m2 multiply by 0.1

The dataset was predicted spatially by digital soil mapping approach using random forest model. Data sources (observation data) was the National Forest Soil Carbon Inventory in Japan (NFSCI), which was carried out throughout Japanese forest (ca. 230 000 km2 , approximately two-thirds of the nation's land) across 2379 sites from 2006 to 2010. All files internally compressed using "COMPRESS=DEFLATE" creation option in GDAL.