Before choosing a presentation aspect ratio
Aspect ratio is the proportion of a slide’s width to its height. When choosing 16:9 or 4:3 for a presentation, first decide where and how it will be shown. Don’t assume 16:9 is the right choice for everyone just because widescreen displays are common; recording with a camera, an organization’s template, or event guidelines may call for a different option.
Start with these questions:
- Does the event or organization require a specific ratio or template?
- Will the presentation fill the screen, or will it be shown alongside the presenter’s camera feed?
- Will the recording include voice-over only, or will the presenter also appear on camera?
- What format must the file be delivered in?
If the event has an explicit requirement, follow it before considering general recommendations. For example, Georgetown’s ADRCon 2025 requires 16:9 for oral presentations and specifies how to check the ratio in PowerPoint. This is a rule for that event; it does not automatically apply to other presentations: ADRCon 2025 presentation guidelines.
Choose between 16:9 and 4:3 based on context
Don’t choose 16:9 just because it looks “modern.” ASU’s video lecture guide recommends considering a 4:3 ratio if the presenter will appear on screen, and keeping the default 16:9 ratio if the recording will include voice-over only. This recommendation applies to the recording context described in the guide; check the guidelines for your own organization or recording setup as well: ASU guide to recording video lectures.
ASU’s studio preparation guide also recommends 4:3 slides for its own recording setup, specifying that two-thirds of the screen will be used for content and one-third for the presenter’s image. So don’t assume 4:3 is necessary for every presentation that uses a camera: ASU presentation preparation guide.
In short, consider mandatory technical requirements first, then the camera and screen setup. If these don’t point to a particular ratio, decide by testing your presentation in the setup where you’ll show it.
Prepare to change the ratio
Before making a change, save a copy of your presentation file. That way, you’ll still have the original version if the layout at the new size doesn’t look as expected. Also find the event template and delivery format instructions, if there are any. Menu names can vary between applications, so don’t follow Google Slides’ steps for another product; check the current help for the application you use.
In Google Slides, open the presentation on a computer and go to File > Page setup. You can choose standard 4:3, widescreen 16:9, widescreen 16:10, or a custom size. Confirm the options and steps you see in the product’s official help page. These steps are specific to Google Slides; don’t assume the same menu is available in other presentation applications.
Apply the ratio and review every slide
First apply the ratio you want, then review the entire presentation in order. You may need to rearrange text, images, or charts after the change. On each slide, check headings, text boxes, diagram labels, logos, image crops, and footnotes. Don’t place important information too close to the edges, or crop a meaningful part of an image just to make it fit the new frame.
Rather than automatically filling any empty space with new content, focus first on preserving readability and meaning. If necessary, realign elements or shorten the text. If you’re delivering the presentation as a PDF, open the exported file and check how it looks; keep the editable presentation file too. Don’t assume that exporting will automatically fix the ratio or layout.
Hypothetical example: online lesson
Hypothetical scenario: An instructor is preparing a lesson presentation to show by sharing a 16:9 screen and later record with voice-over. The organization doesn’t specify a particular ratio, and the instructor’s camera feed won’t appear on screen. Under these conditions, the instructor may consider 16:9 as a starting choice; it isn’t a fixed rule for all lesson recordings.
Imagine a completely fictional “water cycle” slide with a short heading and three key concepts on the left, and a diagram of the cycle on the right. After choosing the ratio, the instructor checks that the diagram labels are readable and that no important parts have been cut off. If a label isn’t visible, the instructor adjusts the text or layout rather than cropping the diagram in a way that changes its meaning. Finally, the instructor checks the presentation on the screen where it will be shown or in the recording preview. This example doesn’t claim that a particular application has a specific feature; it illustrates how to test the ratio in relation to the content and how it will be shown.
Final checklist
- The ratio follows the event or organization’s guidelines.
- If a camera will be used, the recommendation for the recording setup has been checked.
- Text, charts, and important visual details are visible on every slide.
- The exported delivery file has been opened and reviewed.
- A copy of the original presentation file has been kept.
For more steps on choosing a size in Google Slides, see Choosing an aspect ratio in Google Slides; for a readable image, see Choosing a resolution for presentation slides.
Frequently asked questions
Can I change a presentation’s aspect ratio later?
You can change it if your application offers this setting. Review every slide afterward, and confirm the relevant steps in the application’s current help documentation.
Is 16:9 the right choice for every presentation?
No. Consider the event or organization’s guidelines, the target display, and whether the camera feed will appear alongside the slides. If you’re unsure, check the presentation in the actual display setup or in a preview.
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