What exactly is "actual size"?

[TypoMan23]

My PDF at "actual size" shown in Acrobat Pro is a different size to that displayed in Apple's Preview.

Why are the sizes so different and what exactly is "actual size"?

Thank you.

[JR Boulay]

Same answer as for your other question:

https://community.adobe.com/t5/acrobat-discussions/colours-wildly-different-between-acrobat-pro-dc-a...

[Test Screen Name]

And a supplement: in some apps, it tries to work out what size you screen is. In some apps it's fixed. In some apps you can choose what size to use. None of this works with projectors! Look under Page Display and choose Custom Resolution. Not much point asking us to compare with Preview, as we avoid it like the plague.

[TypoMan23]

Thanks for the reply, much appreciated.

It's also my clients who are most likely using Preview and do not have Acrobat Pro. I guess I have no way of controlling what they view my PDFs in...

[Test Screen Name]

Generally, no. You can tell them to use Acrobat Reader, but many will say "this seems to work just fine, I'll ignore that". Only in a business setting where you have authority over how people work can you have much impact.