Illustrator- px to pdf conversion

[Kelbryn24752630tbrp]

So I have had this issue come up a few times while working on projects like this. I was creating some billboard designs, all different sizes so I created 5-6 seperate documents all differnt px sizes.

When I am in illustrator, the files are working and I click on document setup and the px sizes & document sizes are correct. But then when I save it as a pdf, or jpg, the sizes are wrong. I think somehow they are getting distroted during the saving process?

HELP.

I have never had this happen and when I go to resize the files in photoshop they lose relsolution and look like poop. :') I really hope it isnt the laptop im working on...but could be. Someone let me know what you think. 

[Monika Gause]

For a billboard design which is going to be printed, px is not an appropriate measurement unit.

[Kelbryn24752630tbrp]

 @Monika Gause Thank you for the input. It is not a billboard that is going to be printed. They are billbaords that shuffle through multiple deisgns at a time. So at a basketball game or a billboard your drive by that is rotating between ads. They sent me the file sizes required. I just can not get them to save appropriately from Illustrator. 😞 I tried to reduce the resolution which obviously makes them look not as good and that still didn't help with the size change. 

[Monika Gause · Accepted solution]

So they gave you the pixel dimensions?

In order to export those pixel dimensions, export at 72 ppi. And that's that. Don't zoom in after exporting the pixel file.

[Kelbryn24752630tbrp]

Okay I am gonna trust you haha. All they gave me were 6 different pixel dimensions so I will save as 72 dpi. Thank you!