Many people use PowerPoint (PPT) to design carousel-style slide posts for Instagram. The problem is that PowerPoint's default slide is 16:9 (landscape), which does not fit Instagram's vertical feed. You need to change the slide size first.
Common aspect ratios for Instagram carousel posts
| Ratio | Pixels | PPT cm (96 dpi) | Notes |
|---|---|---|---|
| 4:5 | 1080 × 1350 | W 28.58 × H 35.72 | Takes up the most space in the feed |
| 1:1 | 1080 × 1080 | W 28.58 × H 28.58 | Square, safe choice |
| 4:3 | 1080 × 810 | W 28.58 × H 21.43 | Landscape, for blogs |
How to change slide size in PowerPoint
- Open PowerPoint.
- Go to Design tab → Slide Size → Custom Slide Size.
- Enter 28.58 cm for Width and 35.72 cm for Height. (This equals 1080 × 1350 px.)
- When prompted, choose Ensure Fit.
- You now have a vertical slide. Add your text and images.
PowerPoint uses centimeters, and the default export resolution is 96 dpi. 28.58 cm × 96 dpi ÷ 2.54 = 1080 px. If you need higher resolution, set the export DPI to 192 (2×) for a 2160 px wide image.
Exporting as images
- Go to File → Export → Change File Type.
- Select PNG and click "Save As."
- Choose "All Slides" to save each slide as a separate PNG.
- Check that the exported images are 1080 × 1350 px. (They should be at the default 96 dpi.)
PowerPoint vs online tools
PowerPoint is convenient if you already know it, but the cm-to-px conversion is tedious and you have to verify the export resolution manually. With the Carousel Post Maker, you design directly on a pixel-based canvas and save as PNG with no conversion step.
Checklist
- Did you change the slide size to Custom?
- For Instagram: 4:5 (28.58 × 35.72 cm). For blogs: 4:3 (28.58 × 21.43 cm)?
- Did you export as PNG with a resolution of at least 1080 px wide?
- Is the file size under Instagram's 30 MB limit?
FAQ
How do I enter pixel dimensions in PowerPoint?
PowerPoint uses centimeters (or inches), so you need to convert. At 96 dpi: 1080 px = 28.58 cm, 1350 px = 35.72 cm.
What aspect ratio is best for Instagram carousel posts?
4:5 (1080 × 1350 px) takes up the most feed space. 1:1 (1080 × 1080 px) is also popular.
Is there a tool that creates carousel posts without PowerPoint?
Yes. The Carousel Post Maker on Ttukttak Design lets you design on a pixel-based canvas and export directly as PNG.