Lesson 4 – Designing slides so they are easy to see

One of the common complaints of audiences is that they can’t see what the presenter has put on the slide. Either the colors don’t show up easily, the font is hard to read, or the text is way too small to read. If the audience can’t see the information on your slide, they can’t understand your message. In today’s lesson I’ll be talking about selecting colors and fonts that make it easy for the audience to see the content on your slide.

Some of you may not think this lesson applies to you because you have a template that your organization forces you to use that has pre-selected colors and fonts. This lesson will still be valuable because you will be making choices of colors and fonts for graphs, diagrams, and text boxes, which may or may not be set correctly in your organization’s template. (BTW, if you know the person in charge of creating and maintaining the template, tell them to check out this book, Building PowerPoint Templates Step by Step with the Experts. It is THE guide to properly constructing a template that works.)

Select colors that have contrast

Let’s start with color choice. The single most important factor when selecting colors is that they have enough contrast. When a text color and a background color have enough contrast, the letters “float” on top of the background and are easy to see. Do you need to have design or graphics training to be able to tell if two colors you have chosen have enough contrast? No. Fortunately, an international standards organization has created two tests that determine if two colors have enough contrast. I took these tests and developed the Color Contrast Calculator online tool so that you can put in the two colors you want to use and it will do the calculations for you. Use it for text and background colors or for colors you want to put beside each other, such as in a pie chart. Try it out and see how it helps confirm your color choices will work for the audience.

Select a standard sans-serif font

Next I want to deal with font choice. There are so many fonts out there. Which one should you choose? My recommendation is to use a standard sans-serif font like Arial or Calibri. Let me explain why I suggest this. First, academic research shows that a sans-serif font is easier to see when projected. In my workshops I show the participants a slide that has the same text in a script font, a serif font like Times New Roman, and the standard san-serif fonts of Arial and Calibri. Almost everyone says that the sans-serif fonts are much easier to read. Can you choose any sans-serif font? I suggest a standard one because when you take your presentation to another computer or you e-mail it to someone, the text will look the same because all computers have these standard fonts. If you use a downloaded font, it will get substituted on computers that don’t have that font, and your text may and up garbled or out of place.

Use a font size that is big enough to see

Now that you have selected a font, how big does it need to be? Certainly bigger than the smallest font I have seen used on a slide – 4 point! (I couldn’t make that up if I tried!) I wasn’t satisfied with the various rules of thumb that are out there regarding font size, so I decided a few years ago to do the research so that we had a basis for selecting a font size. I based my analysis on the standards that optometrists use for functional vision and the standards that are used to create road signs that keep drivers safe. I figured if it was good enough to save lives on the road, it should be good enough for us as presenters. The real answer to how big of a font you need to use is, “It depends.” It depends on the size of screen and the distance that the audience is from that screen. So I created tables that will help you know what font size you should select. There are tables for the standard 4×3 projectors and the newer 16×9 flat screen TVs that you can access here. If you want a short answer that works in almost all situations, use a 36-44 point font for the headline and 24-32 point font for slide text. I sometimes will use an 18 point font for a text label on a graph or diagram, but smaller than 18 point and it becomes difficult to see.

Here are some additional resources that will help you with slide design:

Choose a boring font

Three steps to reformat a presentation with a new slide design

How to create a consistent look when many sources are contributing slides to a presentation



This is one of the lessons in my free seven day e-course that will help you create more effective PowerPoint presentations. If you reached this page from a web search, you can sign up to get all seven e-mails delivered to your Inbox by filling in the information in the form located at the top right of this page.

By Dave Paradi

Dave Paradi has over twenty-two years of experience delivering customized training workshops to help business professionals improve their presentations. He has written ten books and over 600 articles on the topic of effective presentations and his ideas have appeared in publications around the world. His focus is on helping corporate professionals visually communicate the messages in their data so they don't overwhelm and confuse executives. Dave is one of fewer than ten people in North America recognized by Microsoft with the Most Valuable Professional Award for his contributions to the Excel, PowerPoint, and Teams communities. His articles and videos on virtual presenting have been viewed over 4.8 million times and liked over 17,000 times on YouTube.