Convert coordinates from Guam 1963 (EPSG:4675) to NAD83(HARN) (EPSG:4152) — official EPSG transformation parameters, accuracy and area of use, with a free in-browser converter.
The EPSG Geodetic Parameter Dataset defines 2 transformations between Guam 1963 (EPSG:4675) and NAD83(HARN) (EPSG:4152). Each applies to a specific area — pick the one whose area of use covers your data.
Grid files: guhpgn.lasguhpgn.los
NADCON method which expects longitudes positive west; EPSG GeogCRSs Guam 1963 and NAD83(HARN) (codes 4675 and 4152) have longitudes positive east. Can be used as approximation for tfm between Guam 1963 and WGS 84 - see tfm code 1069.
Grid files: nadcon5.gu63.nad83_1993.guamcnmi.lat.trn.20160901.bnadcon5.gu63.nad83_1993.guamcnmi.lon.trn.20160901.b
Uses NADCON5 method which expects longitudes positive east in range 0-360°; EPSG source and target CRSs have longitudes positive east in range -180° to +180°.
The same transformation with common GIS tools and libraries:
from pyproj import Transformer
transformer = Transformer.from_crs("EPSG:4675", "EPSG:4152", always_xy=True)
x, y = transformer.transform(-73.9857, 40.7484)
print(x, y)geographic system using latitude and longitude on an ellipsoid · Area of use: Pacific - Guam and NMI - onshore
+proj=longlat +ellps=clrk66 +no_defs +type=crsMore about EPSG:4675 →
geographic system using latitude and longitude on an ellipsoid · Area of use: USA - HARN
+proj=longlat +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +no_defs +type=crsMore about EPSG:4152 →