The short answer: in a blank PowerPoint deck, open Design → Slide Size → Custom Slide Size (on a Mac, Page Setup) and set 11.25 × 14.0625 inches, which is 1080 × 1350 px in 4:5 portrait. Build one slide per idea, export a PDF that contains only the slides, and upload it to LinkedIn as a document. LinkedIn accepts PPTX files too, but it recommends PDF for the best quality.
The size to type into PowerPoint
| Shape | Width × height | Note |
|---|---|---|
| Portrait 4:5 | 11.25 × 14.0625 in | Exactly 1080 × 1350 px at 96 px per inch |
| Portrait 4:5 | 8 × 10 in | The same shape in rounder numbers; 10.8 × 13.5 in works too |
| Square 1:1 | 11.25 × 11.25 in | 1080 × 1080 px |
Why inches: Microsoft's help says the desktop apps accept inches, centimeters or pixels, but the limits it lists do not agree with each other (1 to 56 inches, yet 120 to 720 pixels), and PowerPoint for the web takes inches only. Inches work in every version. A PDF keeps the shape of the slide, so any 4:5 pair from the table gives the same carousel.
Why 4:5: PowerPoint starts every new deck at 16:9 widescreen, which on a phone is a short strip with small text. A 4:5 portrait page fills far more of the screen. LinkedIn publishes no carousel size; 1080 × 1350 is the convention, built on the 1080 px width LinkedIn recommends for images and the 4:5 maximum it displays them at. More in LinkedIn carousel size.
1. Set the slide size first
- Create a blank presentation.
- On Windows and in PowerPoint for the web, choose Design → Slide Size → Custom Slide Size. On a Mac, choose Design → Slide Size → Page Setup (in older Mac versions, File → Page Setup).
- Type the width and height. On Windows and Mac, add the unit after a space, for example 11.25 in; the web app takes inches anyway. A height larger than the width makes the slides portrait.
- Click OK.
Do it before you add anything. On a deck that already has content, PowerPoint asks whether to Maximize, which can push content off the slide, or Ensure Fit, which shrinks it (on a Mac the choice is to scale or not). Either way you end up fixing every slide by hand.
One thing PowerPoint gets right for carousels: it cannot give a single slide its own size. Every slide in a deck is the same size, so every page of your PDF will match, as LinkedIn asks. If you make carousels often, save the blank 4:5 deck as a theme (Design, the More arrow of the Themes group, Save Current Theme), then right-click it under Custom and choose Set as Default Theme. New decks then start at 4:5.
2. Build the slides
- Keep one idea per slide. For type sizes, contrast and margins, see LinkedIn carousel design; for the first, middle and last slides, see how to structure a LinkedIn carousel.
- Build one content slide fully, then duplicate it for the rest, so margins and text sizes match on every slide.
- Put the slides in reading order by dragging the thumbnails on the left. Check the order again in the exported PDF.
- Delete, don't hide. A hidden slide stays in the file and is only skipped during a slide show. Delete slides that do not belong in the carousel, so they cannot slip into the PDF.
- Leave out animations and transitions. LinkedIn shows documents as still pages, so animations and videos become static images. Every slide has to work as a still.
- Keep photos sharp. PowerPoint compresses images by default. On Windows, before you export, open File → Options → Advanced, and under Image Size and Quality tick Do not compress images in file and set Default resolution to High fidelity. The setting applies to the open file.
3. Export the PDF
Windows
- Choose File → Export → Create PDF/XPS Document → Create PDF/XPS.
- Pick a name and a folder.
- Next to Optimize for, choose Standard. Minimum size makes a smaller file at lower quality.
- Click Options…, keep the range on All, set Publish what to Slides (not notes pages or handouts), and leave the boxes for frame slides, hidden slides, comments and ink unticked.
- Click OK, then Publish.
Mac
Choose File → Save As (or File → Export) and set File Format to PDF. There are no options for notes, hidden slides or file size. Quality is set under PowerPoint → Preferences → General → Print Quality (Paper/PDF); it is High by default, so leave it there. PDFs saved on a Mac drop hyperlinks. If your slides have links, save the deck to OneDrive, open it in PowerPoint for the web and download the PDF there.
PowerPoint for the web
Choose File → Export → Download as PDF. There is nothing to set. Microsoft says PDFs made on the web keep hyperlinks and tend to be smaller.
Whichever you use, open the PDF before you post: one page per slide, in order, no notes, nothing you meant to leave out.
4. Upload the PDF, not the deck
LinkedIn accepts PPT and PPTX files as documents, and readers can download them as a PDF. Upload the PDF you made anyway: LinkedIn itself recommends PDF for the best quality, and it does not say how it treats fonts when it converts a deck. A PDF you checked removes the question. If you do upload the PPTX, embed your fonts first with File → Options → Save → Embed fonts in the file (on a Mac, in Preferences); some fonts cannot be embedded because of their license. The posting steps are in how to post a carousel on LinkedIn.
The free version is enough
You do not need a Microsoft 365 subscription for this. PowerPoint for the web is free with a Microsoft account; the desktop apps need Microsoft 365 or a license. The web version covers every step above, with two limits: slide sizes are typed in inches only, and the PDF download has no quality or range options. For a carousel, neither matters.
PowerPoint pitfalls and fixes
| Problem | Fix |
|---|---|
| Each PDF page shows a slide with notes under it | Publish what was set to Notes pages. Set it to Slides and export again |
| Slides you hid appear in the PDF | The hidden slides box in Options is ticked. Untick it, or delete those slides |
| Photos look blurry | Turn off image compression, use High fidelity and Optimize for Standard, not Minimum size. On a Mac, keep Print Quality on High |
| Content is cut off or tiny after changing the size | Maximize or Ensure Fit rescaled it. Set the size on a blank deck and rebuild the slides there |
| Fonts look different on LinkedIn | Upload a PDF you exported yourself instead of the PPTX |
| Links do not work in the downloaded PDF | Mac PDFs drop links. Export from Windows or PowerPoint for the web |
| An animation shows as a still frame | LinkedIn shows documents as static pages. Design each slide to work without motion |
The shorter way
cropdot starts from a topic instead of a blank deck. Type the topic or paste your notes and it drafts the slides, aiming for 6 to 10 with a hook on the first one. Export → Download PDF gives one page per slide at 1080 × 1350, every page the same size, with no slide size, notes pages or hidden slides to think about.
PowerPoint is the better choice when the carousel has to use your company's template and fonts, or when the material already lives in a deck. cropdot has six fonts, no custom font upload and no import from PowerPoint or any other file, so it will not reuse slides you already have.
Sources
- Microsoft Support: Change the size of your slides, Save PowerPoint presentations as PDF files, Hide or show a slide, PowerPoint Options (Advanced), Benefits of embedding custom fonts, Microsoft 365 and the free web apps.
- I need to create a PowerPoint that is 7296 x 1080, Microsoft Q&A, on 96 pixels per inch (answer by John Korchok).
- LinkedIn Help: Upload and share documents.
Checked on October 2, 2026.