LinkedIn carousels: why they are PDFs, and what changes from Instagram

The difference that trips everyone up

On Instagram, a carousel is a post with several images. On LinkedIn it is a DOCUMENT: you upload a multi-page PDF and the network turns it into something swipeable in the feed.

So "posting several images" is not the same thing there. Select five PNGs and you get a gallery — different behaviour, different look. The button you want is the document one.

The practical consequence: files coming out of a carousel editor need to be merged into a PDF before uploading. It is one extra step, and it is the step people find out about at the wrong moment.

Format, pages and limits

What holds today:

• Size: 1080 × 1350 (4:5) takes the most phone screen, same as Instagram. Square (1080 × 1080) also works and is common in more formal content.
• Pages: the cap is 300, and the cap is not the target. Between 5 and 10 is where most good LinkedIn carousels live.
• File: PDF, up to 100 MB. PDF is what renders identically across devices — a converted slide deck tends to arrive with substituted fonts.

Fonts are the part that breaks most often: if they are not embedded in the PDF, LinkedIn draws with something else and the layout slides. Exporting with embedded fonts fixes it, and it is the default in most tools.

What changes in the content

The reader is the same human being in a different context, and context changes what works.

On LinkedIn, a hook that promises a professional outcome beats one that promises a trick. "The pricing mistake that cost me three clients" outperforms "5 productivity hacks", because the reader is there measuring whether you know what you are talking about.

There is also more tolerance for text. The LinkedIn feed is read more slowly than Instagram's, so a card with two or three sentences does not repel the way it would there. That is not a licence to fill: one idea per page still holds.

Reusing your Instagram carousel: what carries over

More than you would think, as long as three things are adjusted.

• The first card. An Instagram hook is usually too short and too emotional for LinkedIn. Rewrite it promising the professional consequence.
• The closing card. "Follow me" lands badly there. An invitation to share an experience does better, because comments are what LinkedIn distributes.
• The caption. It weighs more than on Instagram — the first two lines decide whether anyone opens the document. Worth writing a new one rather than reusing.

What does not need changing is the middle. If each card already held one idea, it crosses between the two networks untouched.

How to merge the images into a PDF

If your tool exports PNG — which is the case with SwipeSwipe today, images rather than PDF — the missing step takes about a minute.

On Windows, select the images in order, right-click and choose print, with "Microsoft Print to PDF" as the printer. On a Mac, open them all in Preview, order them in the sidebar and export as PDF.

What needs attention either way is the ORDER and the margins: printing tends to add a white border, and a white border around a carousel designed to the edge ruins the effect. Choosing "actual size" or zero margins avoids it.