Can I can semi accurately measure distance anywhere while using Equirectangular?

[The King of Nipples]

I would like to use one but the map is has a height to width ratio of 2:1 so one has to be double if there is a way where it is all the same please let me know

[waldronate]

The Equirectangular projection (in the plate caree or geographic aspect most commonly used) allocates equal amounts of angular resolution (latitude and longitude) to linear image resolution (pixels wide and high). The distance from one point on the equator all the way around the world to that point again is 360 degrees. The distance from the north pole to the south pole is 180 degrees and then back around to the north pole is another 180 degrees. An Equirectangular map has a vertical extent from the north pole to the south pole (180 degrees) and a horizontal extent from a point on the equator all the way around the globe back to that point (360 degrees). That's where the 2:1 ratio comes from. If you measure on your globe, it's 24000-odd miles around the equator and 12000-odd miles from pole to pole. That makes the resolution the same vertically at every point on the map (12000 miles / 180 degrees) as it is on the equator of the map (24000 miles / 360 degrees).

[Azélor]

A 2:1 ratio means the image width is twice the height but the vertical and horizontal scale are the same. The distance is doubled but the scale remains the same.
Well assuming you are using an equirectangular projection. Different projections have different ratio.

Van der Grinten for instance is a 1:1 ratio projection. https://en.wikipedia.org/wiki/Van_de...ten_projection
With this projection, youyr reasoning would make sense but not with equirectangular unless

[The King of Nipples]

Oh this was my problem, I thought it was supposed to also be the same distance around as it was from pole to pole thanks!

[The King of Nipples]

If I were to just move a continent up to the equator temporarily would I then be able to get a feel for how big it is on the map?

[waldronate]

If I were to just move a continent up to the equator temporarily would I then be able to get a feel for how big it is on the map?

Only if you reproject it properly. https://www.maptoglobe.com/ might be helpful if you have an Equirectangular map.