How To: Adjusting your Files to 300dpi Using Adobe Illustrator

When prepping your files for book printing, PufferPrint asks that files are saved and shared in at least 300dpi.  Maybe you’re new to self-publishing, or prepping book files for custom book printing, don’t worry we’ve got your back!  In this post, we’ll review how to convert your files to the proper resolution to optimize for PufferPrint’s offset printing services. 

What does dpi mean?

Dpi refers to dots per inch when printing a file. Because printing a book uses layers of small colored dots to create a full image, determining how many dots per inch your printer will use helps ensure your files are printed correctly. 300dpi is the standard for offset printing to ensure a good quality outcome.

When talking about formatting your files on a computer, this will show up as ppi (pixels per inch) as it is related to the pixels on your screen. The ppi ratio will then be used and converted as the dpi when it is physically printed. Adobe programs generally automate a document as 72ppi to save file space, so it is important to make these changes before sending files to be printed.

Before checking the ppi of your document, you first need to make sure your file is in CMYK color mode. If you don’t know what that means or how to confirm your file is in the right color mode, check out our previous How-To blog post “Using Adobe Suite to Convert RGB to CMYK in 8 Steps.”

If somehow you found this post but don’t own Adobe Suite programs or need additional help formatting your files, PufferPrint offers print formatting and E-book conversion services! Click here or email info@pufferprint.com today to get started and leave the formatting to us! 

How can I adjust my file?

This tutorial is done using Adobe Illustrator as it will give you the best results. We don’t recommend using InDesign for ppi conversions as this program is a vector program and can result in lower quality results. Photoshop can also be used to adjust ppi when exporting image files (such as .jpg or .png) not .pdf files. The video in this tutorial was screen recorded on an HP computer, though the process is the same on a Mac or other PCs.

There are two ways to adjust ppi on an Illustrator document. One of them being while you are currently working on your document, and the other while you are exporting your document (though you can only change the ppi through the export screen if you are exporting as a .png or .jpg. To convert a .pdf file you will need to change ppi settings before saving). Overall, It’s better to be working in the correct ppi throughout the entire process to ensure the quality of images and your file altogether. 

Stay tuned for our next How-To tutorial for getting your files ready to print by setting your text to 1c black.