I need help,
in layout I have a document set to A3 paper, but when the page is zoomed 100% (at the bottom right next to Measurement), the document is small. The zoom is not 100%, so I have no idea what it will look like when printing.
Thanks
Hi,
You have a few options here.
The first is to zoom the view to 100% and turn on the ruler settings… this should give you an idea as to how tall your text is standing… >Text >Show Rulers.
I used to make a reference printout… that was basically just a page full of various line weights, and text sizes, and that went a long way towards saving me a lot of wasted paper due to poor page layouts.
In short time you’ll come up with a combination of settings that you like to use and you’ll probably remember how tall you want various type to stand, or what line weights you want to call upon.
There’s a lot of fun to be found here. Because a heavy line weight can also be made lighter by changing color rather than size. For example: by using a dark gray (rather than black). Very often 80 - 90% gray scale color is a good way to go… It’s reads as being black, but the harsh darkness of black is eased off a little bit… and the finished results look a bit more polished — and sit better upon the page.
So that test print I was mentioning, actually had the standard line weights, and font sizes set in three different colors. But you should of course follow your own instincts on this if you even try it.
You can always temporarily change the document size of your project and run a test print to a smaller paper size. You have to do a bit of repositioning so that you’re capturing the area of your layout your most concerned about. And this is probably a good reason for simply making copy of your file and working from that, and deleting it when your done.
Where are ruler settings?
It’s at the bottom of the Text menu.
and could arguably be better placed under the View menu but that’s a different issue.
What is the resolution of your monitor? On my desktop machine, 86% seems to be right when I measure something on screen with a ruler held up to it.
@JimD, Rulers are a Mac thing. 
I didn’t remember that, Thanks Dave.
In that case I’ll throw in a plug for a third party ruler app that I used to use and love called a Ruler for Windows. https://www.arulerforwindows.com/
I have windows 10 and I don’t have a ruler 
I have 3 monitors - the main one is 2560x1440, the other the same and the third 2048x1152
On the third monitor, the 100% zoom is about 1cm smaller than the actual print size. On the main monitor, about 5 cm (at page A4)
As I said, rulers are a Mac thing.
The on screen display is affected by the resolution/pixel width of the monitor. Easiest thing to do is grab a ruler, a real one, not a virtual one, and measure a know length on the screen. I added a sticky note on my display to remind me that 86% shows the document at full size.