The Blueprint for High-Converting LinkedIn Ad Sizes

In B2B digital marketing, creative strategy gets all the attention, but technical execution often dictates success. You can write brilliant copy and craft a compelling offer, but if your asset gets awkwardly cropped in the mobile feed or exports as a blurry, pixelated mess, your ad spend goes straight down the drain.

LinkedIn is a high-CPM platform, which means every impression counts. Ensuring your creative assets match LinkedIn’s exact specs, ratios, and safe zones isn’t just about compliance—it’s about maximizing visual real estate to drive higher click-through rates (CTR).

Sponsored Content (Feed Ads)

Feed-based formats appear directly in a user’s main newsfeed. Because over 50% of LinkedIn traffic occurs on mobile devices, choosing formats that maximize vertical screen real estate is essential.

1. Single Image Ads

Single Image Ads remain the workhorse of B2B campaigns. They appear seamlessly in the feed on both desktop and mobile.

| Orientation | Recommended Resolution | Aspect Ratio | Maximum File Size | Supported Formats |
| :— | :— | :— | :— | :— |
| Square (Best for Mobile) | $1200 times 1200text{ px}$ | $1:1$ | 5 MB | JPG, PNG, GIF |
| Landscape (Classic) | $1200 times 628text{ px}$ | $1.91:1$ | 5 MB | JPG, PNG, GIF |
| Vertical (Mobile-Only) | $720 times 900text{ px}$ | $4:5$ | 5 MB | JPG, PNG, GIF |

Pro Tip: While $1200 times 628text{ px}$ used to be the industry default, switching to a $1:1$ Square or $4:5$ Vertical layout gives your ad up to 78% more vertical space on mobile feeds, making it much harder for users to scroll past.

2. Carousel Ads

Carousel Ads allow users to swipe through a series of cards (2 to 10 cards per ad unit). They are ideal for step-by-step guides, feature breakdowns, or showcasing multiple client testimonials.

• Recommended Resolution: $1080 times 1080text{ px}$ per card
• Aspect Ratio: $1:1$ Square
• File Types: JPG, PNG, or non-animated GIF
• Max File Size: 10 MB per card
• Card Count: Minimum 2, maximum 10

3. Video Ads

Video creative on LinkedIn requires precise attention to aspect ratio and frame rates to prevent compression artifacts or pillarboxing.

• Aspect Ratios:
  • Square: $1080 times 1080text{ px}$ ($1:1$)
  • Landscape: $1920 times 1080text{ px}$ ($16:9$)
  • Vertical (Feed): $1080 times 1350text{ px}$ ($4:5$)
  • Full Vertical: $1080 times 1920text{ px}$ ($9:16$)
• File Format: MP4 (AAC audio, H.264 video encoding)
• File Size: Minimum 75 KB, maximum 500 MB
• Video Duration: 3 seconds to 30 minutes (High-performing ads typically run 15 to 30 seconds)
• Frame Rate: Up to 30 fps

Lead Generation & Document Formats

For high-intent B2B conversion campaigns, LinkedIn offers specialized native units that eliminate the need for an external landing page.

Document Ads (Lead Magnet Powerhouses)

Document Ads allow prospects to read or download PDFs, slide decks, or whitepapers directly within their feed.

• Supported Formats: PDF, DOC/DOCX, PPT/PPTX
• Maximum File Size: 100 MB
• Page Limit: Up to 300 pages (First 3–5 pages act as the visual preview hook)
• Aspect Ratios: Standard PDF dimensions work seamlessly (Vertical $A4$ or $8.5 times 11text{ inches}$ is recommended for mobile readability).

Desktop & Right-Rail Formats

These cost-effective placements appear exclusively on desktop viewports along the right column or in messaging interfaces. While they deliver lower engagement rates overall, they offer low CPMs and consistent brand awareness.

1. Text Ads

Displayed along the top or right side of the desktop feed.

• Logo Image Size: $100 times 100text{ px}$ ($1:1$)
• Max File Size: 2 MB (JPG or PNG)
• Copy Specs: Headline (max 25 chars), Description (max 75 chars)

2. Spotlight & Dynamic Ads

Personalized ad units that dynamically pull the target viewer’s profile picture alongside your company logo.

• Company Logo: $100 times 100text{ px}$ (PNG or JPG)
• Custom Background (Optional): $300 times 250text{ px}$
• Max File Size: 2 MB

3. Conversation & Message Ad Banners

When running Sponsored Messaging, you can pair your message with an optional desktop companion banner to maintain brand visibility while the user reads.

• Banner Dimension: $300 times 250text{ px}$
• File Size & Type: 2 MB max; JPG or PNG
• Device Availability: Desktop only

Technical Checklist for Launching LinkedIn Ads

Before pushing creative live to campaign manager, verify your assets against these best practices:

1. Optimize for Mobile First: High-converting images place primary focal points, brand marks, and value propositions near the top-center to prevent mobile UI elements (like reaction buttons or CTA bars) from obscuring content.
2. Export at $2times$ Pixel Density: Render $1080 times 1080text{ px}$ visuals at $2160 times 2160text{ px}$ (while staying under the 5 MB file size limit) to ensure crisp playback on Retina and high-DPI smartphone screens.
3. Embed Captions into Videos: Up to 80% of LinkedIn feed videos are watched without sound. Always include burnt-in subtitles or upload a custom .srt file.
4. Mind Copy Truncation Limits: Keep your primary introductory text under 150 characters for Single Image Ads and 45 characters for Carousel card headlines to ensure your core message is read without requiring a click on “…see more”.