Units on Buffer and Fishnet coming out metric

[RyanSmith_elkhart]

Hi. I'm using current version of ArcGIS Pro. I have a city boundary. I am trying to make a 1 mile buffer around it, and then create a 1000 x 1000 foot grid overlaid over the boundary. I have my units set in my document to feet.

The buffer command has an option where you can choose units, which I've chosen miles. But when I run it and measure it, the actual distance comes out to about 1.3 miles, which is about 2 km.

When I run the fishnet command, it does not have an option where you can select units but I believe it uses the project units. When I run it and measure it, though, it comes out to 3,280 x 3,280 feet, which is actually a square kilometer.

I'm probably missing something obvious but as far as I know everything in the project is set to Imperial units. Thanks in advance.

[DavidPike]

What is the coordinate system of your input city boundary and what is the projection of your map/project?
For the buffer tool, I'd set the 'Method' to 'Geodesic'.  When you measure your buffer, ensure the measurement option is also specified as 'Geodesic'.  I'm thinking you have a Web Mercator of Plate Caree projection for your project/layout and are at a latitude where you're experiencing relatively large planar measurement inaccuracies.

For the fishnet tool, it does not matter how you've set up any project settings to only show imperial.  It's likely your input data coordinate system is in metric metres.  If so, the cell size width and height will be in metres.  The simplest way around this would be to use a cell height/width of 1609.34. 

However it seems strange that your measurement is accurate for the fishnet but not the buffer.  It would be good to see your input data coordinate system, your project/map coordinate system/projection, and any screenshots of your inputs into the tools and the measurements taken after.