If you’ve uploaded a carousel PDF to LinkedIn and watched the text turn blurry or the charts pixelate, you’ve hit the platform’s automatic compression pipeline. LinkedIn doesn’t publish the exact spec, but testing across dozens of uploads reveals a consistent pattern: PDFs get resampled to a maximum width of 1080 pixels per slide, regardless of your original export resolution.
That means exporting at 4K or even 2K is a waste of file size—and often makes compression worse, because LinkedIn’s algorithm has to work harder to downsample a massive file into its fixed output window.
What LinkedIn’s compression pipeline actually does
When you upload a multi-page PDF as a carousel post, LinkedIn converts each page into a raster image. The platform applies lossy JPEG compression at around 80–85% quality, then serves the result at a fixed width of 1080 pixels. Height scales proportionally, but the horizontal cap is hard.
If your original PDF contains vector text or high-res images exported at 300 DPI and 3000 pixels wide, LinkedIn downsamples it. If you export at exactly 1080 pixels wide, LinkedIn still compresses it—but the quality loss is minimal, because there’s no resampling step.
Text suffers most. Small sans-serif fonts at 10–12pt become fuzzy after downsample and compression. Charts with thin grid lines lose definition. Gradients band visibly.
The export settings that survive compression
After testing Canva, Figma, Adobe Illustrator, and Keynote exports, here’s what works:
- Canvas size: 1080 × 1080 pixels for square carousels, or 1080 × 1350 pixels for portrait (4:5 ratio). LinkedIn supports both, but square is more common.
- Export resolution: 72–150 DPI. Anything higher gets downsampled anyway. Save the file size.
- Font size floor: 18pt minimum for body text, 24pt for headlines. Smaller than that and compression blur makes it hard to read on mobile.
- Line weight: 2px minimum for borders, dividers, and chart axes. 1px lines disappear after compression.
- Color mode: RGB, not CMYK. LinkedIn’s pipeline expects screen color space.
If you’re exporting from Canva, choose “PDF Standard” rather than “PDF Print”—the print preset defaults to CMYK and 300 DPI, both of which get mangled. Figma users should export as PDF at 1× scale, not 2× or 3×.
When compression visibly degrades your slides
Three scenarios cause the worst quality loss:
Screenshots of text. If you embed a screenshot of a tweet, email, or dashboard inside your carousel slide, and that screenshot contains small text, compression will blur it twice—once when you captured it, once when LinkedIn resamples the PDF. Better to recreate the layout with live text in your design tool.
Gradients and soft shadows. Subtle gradients band into visible stripes after JPEG compression. Use solid fills or high-contrast gradients (light to dark, not light to slightly-less-light).
Busy backgrounds. Textured or photographic backgrounds behind text create compression artifacts that make the text harder to read. Stick to solid colors or very simple geometric patterns.
File size and upload speed
LinkedIn’s upload interface accepts PDFs up to 100 MB, but anything over 5 MB takes noticeably longer to process—sometimes 30–60 seconds before the post preview renders. A ten-slide carousel exported at 1080px width and 72 DPI typically lands between 800 KB and 2 MB, which uploads and processes in under ten seconds.
If your file is larger than 3 MB, check your export settings. You’re probably rendering at a higher resolution than LinkedIn can use, or embedding uncompressed images inside the PDF.
Most design tools let you compress images before export. In Canva, this happens automatically when you choose “PDF Standard.” In Figma, use the “Flatten” option before exporting. In Illustrator, go to File → Save As → PDF, then set “Compression” to JPEG, Medium quality.
One more thing: LinkedIn’s mobile crop
Even if you export at 1080 × 1080, LinkedIn’s mobile app often crops the top and bottom edges of each slide in the feed preview. Users have to tap through to see the full slide. That means critical text—headlines, CTAs, key data points—should sit in the center 80% of the canvas, not near the edges.
Test your carousel by uploading it as a draft post, then viewing it on your phone before publishing. If your headline gets cut off in the preview, move it down.
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