Convert coordinates from NAD27 (EPSG:4267) to NAD83(CSRS)v2 (EPSG:8237) — official EPSG transformation parameters, accuracy and area of use, with a free in-browser converter.
The EPSG Geodetic Parameter Dataset defines 4 transformations between NAD27 (EPSG:4267) and NAD83(CSRS)v2 (EPSG:8237). Each applies to a specific area — pick the one whose area of use covers your data.
Grid file: NB2783v2.gsb
Introduced in 2011. Precision of 20 cm in area covered by the input data set and 40 cm anywhere else, with the exception of the northwest area of the province (near the border with Quebec) where the precision deteriorates to 80 cm.
Grid file: BC_27_98.GSB
Derived through NAD83(CSRS)v2. Replaced by NAD27 to NAD83(CSRS) (8) (CT code 9113) for CRD, NAD27 to NAD83(CSRS) (9) (CT code 9114) forn north Vancouver Island and NAD27 to NAD83(CSRS) (10) (CT code 9115) for mainland.
Grid file: QUE27-98.gsb
Also found with file name NA27SCRS.GSB. Uses NT method which expects longitudes positive west; EPSG GeogCRSs NAD27 (code 4267) and NAD83(CSRS) (code 4617) have longitudes positive east. Can be taken as an approximate CT NAD27 to WGS 84 - see code 1692.
Grid file: SK27-98.gsb
Can be taken as an approximate transformation NAD27 to WGS 84 - see code 1703.
The same transformation with common GIS tools and libraries:
from pyproj import Transformer
transformer = Transformer.from_crs("EPSG:4267", "EPSG:8237", 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: North America - NAD27
+proj=longlat +datum=NAD27 +no_defs +type=crsMore about EPSG:4267 →
geographic system using latitude and longitude on an ellipsoid · Area of use: Canada
+proj=longlat +ellps=GRS80 +no_defs +type=crsMore about EPSG:8237 →