PDF toolsSlide decks, menus, event programmes and infographics often start life as PDFs, and social networks are picky about what they accept. The reliable route is to convert each page to an image and post the images.
For a carousel (one image per page)
- Open PDF to JPG and add the PDF.
- Choose 150 dpi. An A4 page comes out about 1240 pixels wide, a good match for Instagram's 1080-pixel width.
- Set JPG quality to 85 or 90.
- Press Convert to JPG. Several pages arrive in a ZIP, numbered in order.
Instagram crops tall portrait images, and an A4 page (about 1:1.41) is taller than any portrait ratio it accepts, so the top and bottom get cut. If you're designing for Instagram, start from a square page instead: PDF Studio has a square social post size and can download pages directly as PNG or JPG.
For a single long image
Group chats and some messaging apps handle one tall image better than ten separate ones. PDF to long image stacks every page into one picture, with a gap between pages if you like. Keep the resolution at 100 dpi for long documents; browsers can't create images taller than about 32,000 pixels.
LinkedIn document posts
LinkedIn lets you upload a PDF directly as a "document" post, which shows as a swipeable carousel. It's a good option for decks. Keep the file under the size limit, give it a clear title (it's shown above the carousel), and make the first page work on its own as a cover, because that's all most people see.
Make text readable on a phone
Pages designed for A4 printing usually have text that's too small on a phone screen. A rule of thumb: if body text is smaller than about 24 pt on a square post, people won't read it. It's usually better to redesign the key pages than to post the print version as-is.