Rectangle Marquee Tool Measurements Incorrect

[seanq47]

This is something that just started recently.  It was working fine before.

While creating web pages, sometimes I will take a screen shot and paste it into a Photoshop document so I can measure things with the rectangle marquee tool.  Now, when I do that - the measurements are displaying larger than they are.  Here's an example:

The CSS of that page sets that box as 56px by 56 px.  When I use the Chrome Developer Tools to inspect the document, it displays that it's a 56px square.  I print screen - paste into a new document in photoshop and use the rectangle marquee tool and it shows that box being 70px.  

I haven't changed any settings.  I'm using the latest version of Photoshop.  It just started doing this.  Any ideas why?

[S_Gans]

It seems the screenshot is adding a few pixels as antialiased pixels. Have you recently updated your OS? I'm not sure where in Windows this option can be turned off for screenshots, but from a brief search, it appears it may be linked to the Font Smoothing setting.