Affinity Designer printed dimensions smaller than screen dimensions

[origami]

I have a design created in Affinity Designer on my MacBook Pro that prints smaller than what is shown on screen.  My design is 3.5” square (as measured by rulers in program) on the screen, but when I print (export) it to pdf, the actual printed image is 3  1/8” .  The screen calculated size should equal printed size.  

[Alfred]

Have you checked that your PDF viewer isn’t scaling the image when printing?

[origami]

Image is not scaled by PDF.

[origami]

I will check with the print store to make sure they are not reducing.

[MikeW]

Just in case, a little info.

If whomever printed it used Acrobat or Reader (or the plug-ins for them that their internal software uses), once someone uses any of the scale options, those options are sticky and will be used the next print. I run into this issue all the time at places like Staples, FedEx Office, etc. As well, some of the digital presses/copiers they use also have a scale option in their set up.

I don't know if that is what is happening to your print job. It got bad enough a couple years ago that this is one of the first things I inform whomever is going to print a piece (unless it is a professional outfit).

All that said, I do know that my direct prints to a PostScript printer are accurate enough I have never measured.