• Lynn Grant

Understanding Annoying File Formats

Updated: Apr 10

November 2, 2019

Picture this: you are in the final countdown of getting everything produced for your upcoming event. Suddenly, a vendor calls to say you have given her the wrong file format for that exhibition poster. If you don't get her the correct file soon, you'll miss your deadline. Sound familiar?

Technology changes so fast these days, there seems to be a new file format invented every day. It's so annoying! If you want to offer the best service to your clients, and keep you vendors happy, understanding extensions (also known as “those buggers at the end of the file name”) is key to your success.

Vector vs. Raster

Don't panic. First off, those sublime suffixes (or extensions) will tell you how the file was saved. Since there are two groups of file types–vector or raster, the simplest way to tell them apart is by those extensions. For example, filename.jpg or filename.pdf are a few of the formats you may see. Each type has specific uses that can’t easily be interchanged. Check out this handy visual chart to help you decode your image files.

EPS, AI, PDF are vector files that can be easily sized up or down without losing the clean lines of the image. You can make that logo small for an embroidered shirt or blow it way up for a printed poster. Don’t expect to edit these files on your computer easily unless you have specialized graphics software.

JPG, GIF, or PNG are raster files that can get tricky, especially when resizing, and are commonly photos or images with millions of colors. GIFs are frequently used in animations, a combo of vector and raster, meant to be seen online. Some PNGs have limited color palettes but can be sized up or down with minimal degradation. Your computer should have simple apps that’ll handle the resizing of files. Additionally, when printing a raster image, files saved in CMYK make it easy for printers to separate out the colors for a four-color press like in a color magazine. RGB raster files are intended for web or screen use only. Good so far? Now you have to consider DPI and PPI.


DPI, dots per inch, refers to print resolution, while PPI, pixels per inch, applies to screen resolution. Both are important determinants whether you publish to print or electronic media. Generally, 300 dpi for print products is required to make your message shine. Images saved at 72dpi for the electronic media will look stunning on screens.

Here is where raster files are annoying. If your images are not saved to their final size of the intended media, you’re in trouble. When you use a low-resolution image destined for the web, but then try to increase its size for a different purpose (and let’s face it, we’ve all done this), you’ll be pulling your hair out when you see the fuzzy, pixelated results. Or if you have a huge TIFF file, there’s no way you’ll want to upload that to a web server as it will take FOREVER to load. Here’s a tip: get into the practice of duplicating the image and resizing those files instead. You can always go back to the original if needed. So what if you end up with ten files that you don’t use, eventually you’ll get hang of it, and your hair will stay on your head!

Intended as a quick overview of file formats, there’s lots more information published online. In case you need immediate help with battling file formats, print out my quick reference chart here. See you at the show!


Lynn Grant Design provides design services in scenic, event and graphics. Her experience designing for media and stage makes her a great fit for your next live event. Contact her at lynngrantdesign@gmail.com