# What is the aspect ratio of a slide? > **Aspect ratio:** The aspect ratio of a slide is the proportion of its width to its height, written as width:height. The standard for presentations today is 16:9 (widescreen), while older decks and some projectors use 4:3. - Source: https://ai-presentations.com/glossary/aspect-ratio/ - Updated: 21 October 2026 - Language: English - German version: https://ai-presentations.com/de/glossar/seitenverhaeltnis/ Also called: 16:9, 4:3, slide ratio, slide size, widescreen **The aspect ratio** of a slide is the proportion of its width to its height, written as width:height. A 16:9 slide is 16 units wide for every 9 units high, whatever size it is shown at. Today 16:9, called widescreen, is the standard for presentations. Older decks and some projectors use 4:3. *A 16:9 slide is 16 units wide for every 9 units high. Here the width holds the labels and the bars, and the height holds the title, the chart and the takeaway. Example with fictional figures.* 3. Inventory and receivables tie up €11.2m, and finished goods alone sit about €1.6m above benchmark ## The common ratios | Ratio | Typical pixels | Size in PowerPoint | Typical use | | ----- | ------------------------- | ----------------------------------- | --------------------------------------------------- | | 16:9 | 1280 × 720 or 1920 × 1080 | 13.333 × 7.5 in (33.867 × 19.05 cm) | Default in current PowerPoint, screens, video calls | | 4:3 | 1024 × 768 | 10 × 7.5 in (25.4 × 19.05 cm) | Older decks, some projectors | A third ratio, 16:10, appears on some laptop screens and projectors. At the same width, a 4:3 slide is a third taller than a 16:9 slide, which is why content does not carry over without changes. ## How to choose and use it 1. **Take 16:9 unless something forces 4:3.** It fits most screens and video calls. Ask whether the room has a 4:3 screen, because a 16:9 slide then shows black bars above and below. 2. **Decide before you build.** In PowerPoint, change it under Design, Slide Size. PowerPoint asks whether to maximize the content or ensure it fits, and afterwards you must check every slide. 3. **Crop pictures, do not stretch them.** A picture in the slide's own ratio fills it without cropping, and a stretched logo looks wrong at once. 4. **Keep one ratio per deck.** Slides pasted from a deck with another ratio shift or scale. > **Tip: With an AI tool** > > The AI picks the page format from your request and defaults to 16:9 for presentations. Its PowerPoint export keeps that shape, 13.33 by 7.5 inches for 16:9. ## Typical mistakes - **Changing the ratio at the end.** Text overflows, pictures distort and the layout needs rework. - **Stretching a picture to fill the slide.** Crop it instead. - **Designing for 16:9 and presenting on 4:3.** The slide shrinks and text becomes small. - **Mixing ratios in one deck.** The slides jump in size when you move between them. ## Related terms The ratio sets the frame. The [slide layout](https://ai-presentations.com/glossary/slide-layout/) decides what goes in it, and [white space](https://ai-presentations.com/glossary/white-space/) decides how much room is left. Your template's ratio is set in the [slide master](https://ai-presentations.com/guides/slide-master/). To check whether text will be readable at the back of the room, use the [font size calculator](https://ai-presentations.com/tools/font-size-calculator/). ## Frequently asked questions ### What is the best aspect ratio for a presentation? 16:9 in almost every case today. It matches most screens, video calls and projectors, and it is the default in current PowerPoint. Use 4:3 only if the room's equipment or an existing template requires it. ### What size is a 16:9 slide in PowerPoint? 13.333 by 7.5 inches, which is 33.867 by 19.05 cm. A 4:3 slide measures 10 by 7.5 inches, or 25.4 by 19.05 cm. ### How do I change the aspect ratio in PowerPoint? Open the Design tab, choose Slide Size and pick Standard (4:3), Widescreen (16:9) or Custom Slide Size. PowerPoint asks whether to maximize the content or ensure it fits. Check every slide afterwards, because pictures and text can shift. ### What happens if a 16:9 slide is shown on a 4:3 screen? It appears with black bars above and below, so it fills the width but not the height, and everything looks smaller than intended. Check the room's screen before you present. ## Related pages - [Slide layout](https://ai-presentations.com/glossary/slide-layout/): A slide layout is a template for how content is arranged on a slide: which boxes it has and where they sit. Definition, common layouts and how to choose one. - [White space](https://ai-presentations.com/glossary/white-space/): White space is the empty area around and between elements on a slide. Definition, why it improves clarity and how to use it, with examples and mistakes. - [Slide master in PowerPoint](https://ai-presentations.com/guides/slide-master/): Open, edit and save the slide master in PowerPoint: fonts, colors, logo, layouts, placeholders and footers, with exact menu paths and fixes for common problems. - [Font size calculator](https://ai-presentations.com/tools/font-size-calculator/): Free font size calculator for presentations: enter the screen size and the farthest viewer's distance, get the smallest title, body and footnote size in points. --- ai-presentations.com is published by Slaide (https://www.slaide.de), a sole proprietorship run by Nathalie Scholl in Heilbronn, Germany. [How this site is written, checked and corrected](https://ai-presentations.com/editorial-policy/).