When measuring a line, what coordinate system does the Measure Distance tool use?

[Anonymous User]

When measuring a line, what coordinate system does the Measure Distance tool use?

[DanPatterson]

Measure—ArcGIS Pro | Documentation

lots of options, including planar and geodesic, read the topic for 2D and 3D options for maps and scenes

[Anonymous User]

Unless I missed something, the only mention of coordinate systems on that page is for measuring area. And that section has no mention of which coordinate system is actually used.

I'm trying to figure out how ArcPro determines which coordinate system to use for the measurement.

[ChristopherCounsell · Accepted solution]

The measure tool uses the Coordinate System set in the Map Properties.

You can confirm this by measuring the distance between two cities and then changing the map coordinate system. 

It's what they use in introduction to ArcGIS courses to explain the distortion on projections.

[ssrojas]

I was also wondering about this! I turned off all layers in ArcGIS Pro and used the measuring tool...Still got a measurement. So, I assumed it was from the Coordinate System.