Windows Dpi Scaling Question

[Wish I had 10]

So I started playing fps games about a month or two ago and I wanted to see what sensitivity in game would be similar to my desktop. (I'm on windows 10 btw) so I disabled accel went to the calculator etc etc 2560x1440 400 dpi which is what I thought I played on. 

 

However I didn' realize my monitor display scaling in windows was at 150% (recommended) because it looked similar to my old 1600x900 monitor in terms of icon size and the desktop game client for a game I played. 

 

Because 2560/1600 = 1.6 so I realize now it felt the same because if you blow up 2560 by 50% 1.5x it's almost 1.6x or that' mu thought on it anyways.

 

The problem I have though is that when I went to the dpi analyzer on this site before it took 6.4 inches at 400 dpi 2560x1440 to cross my monitor in the calculator... however 6.3 on the dpi analyzer doesn't show a target at 150% scaling but instead the edge of my screen shows 4.1 inches at that blue target. Now when I pop the scaling down to 100% I can't really see much but 6.3 is the edge on the analyzer.

So 4.2666 inches to cross the desktop at 100% scale is actually 600 dpi. 1.5x 400dpi

Now I'm confused when I want to calculate that sensitivity for a game I'm playing do I need to use 600 dpi in windows/desktop on the calculator or 400? Because in reality wouldn't it be more like 600 dpi due to the fact that windows 10 dpi scaling seems to increase your mouse cursor speed by the same % it's scaled at (not to mention when scaled up always has some consistent mouse accel even through markc's 150% dpi scale windows 10 fix is applied) so in order to get a proper read out of this sites calculator (aswell as no accel) shouldn't you have your dpi scaling to 100% especially on windows 10?

After all I could be wrong about the dpi scaling on windows 10 screwing with your mouse speed and forcing accel upon you but markc's mouse movement recorder shows definite accel like whole columns of red or green and your dpi analyzer wasn' wrong because I tested the distance to cross at 100% and 150% on my mouse pad too and yeah same distance at 150 to cross only does 66% of the monitor in 100 yet the mouse is 400 dpi on each scaling.

 

So my question at the end of the day is to calculate my proper fps sens from my desktop sens at 150% dpi scaling in windows 10 and play on that with no accel ingame then I should:

Use 600 (400x1.5) dpi on the calculator and set my dpi scaling to 100% on windows on my computer before going into said fps game? 

 

And if dpi scaling is such a big issue on windows 10 which it definately is I can tell right after I noticed it wasnt at 100% and I tested around for like 5 minutes. Shouldn't it be an option on the calculator?

[Wish I had 10]

And not only be an option on the calculator but I don' think windows dpi scaling is supposed to mess with cursor speed so shouldn't Microsoft fix that?

Because on my res 400 dpi should cross the screen 6.4. Inches no accel regardless of dpi scaling (isn' it only supposed to make things appear larger?) And it definately causes ridiculous accel having 150% scaling even through markc fix I can tell u put it up to like 1.2k dpi 100% scale Normal response 150% scale it can go half a monitor or a whole monitor of distance depending on how hard you flick? And I use a g903 logitech mouse with no accel so I really doubt it' my mouse plus 0 accel on the same mouse on 100% scale

[DPI Wizard]

I've added a Windows Scaling option to the Windows/Desktop calculation now. Will fix the DPI Analyzer soon.