Which NAD83 to WGS84 transformation does the ArcGIS Javascript API use by default?

[Anonymous User]

I'm trying to replicate the calculations performed by a Javascript application in Python. The calculations are based on the intersection between a set of points (in WGS84) and a polygon (in NAD83). Depending on which transformation I specify in the Python application, the number of points within a given polygon is consistent with the Javascript application for some polygons, and not for others. I believe it I could specify the correct transformation (the one used in the Javascript application) in the Python application, I would get the correct result.

The Javascript application does not specify a transformation, so I am assuming that it uses whichever is the default.

[ABishop]

This is a shot in the dark.. but I think the default is WGS84?

[Anonymous User · Accepted solution]

This didn't turn out to be the problem, but the answer to the original question, according to Esri Canada technical support, is that the JavaScript API uses WGS 1984 (ITRF00) To NAD 1983 (WKID 108190) by default.