Complete Guide to LinkedIn Ad Sizes and Specs for 2026

Running a high-performing B2B campaign on LinkedIn requires more than just a sharp value proposition and precise audience targeting—it demands pixel-perfect creative execution. Upload an image that is slightly off-ratio, and LinkedIn’s automated compressor will crop out your hook, blur your typography, or throw an annoying error right before launch.

Understanding the specific layout dimensions, aspect ratios, and character limits for each major LinkedIn ad format ensures your campaigns look native, professional, and clear across every device.

1. Single Image Ads (Sponsored Content)

Single image ads are the backbone of most LinkedIn campaigns. They appear directly in the user’s feed alongside organic posts and support three distinct aspect ratios depending on your placement strategy.

• Landscape (1.91:1):
  • Recommended Size: $1200 times 628$ pixels
  • Best for: Universal delivery across both desktop and mobile feeds.
• Square (1:1):
  • Recommended Size: $1200 times 1200$ pixels
  • Best for: Maximizing feed real estate on mobile while remaining clean on desktop.
• Vertical (4:5):
  • Recommended Size: $720 times 900$ pixels
  • Best for: Mobile-first feeds (note: vertical ads do not render on desktop feeds).
• Technical Specs: Max file size of 5 MB; accepted formats include JPG, PNG, and non-animated GIF.
• Text Limits: Introductory text under 150 characters (to prevent mobile truncation); headline under 70 characters.

2. Carousel Image Ads

Carousels let you feature a sequence of 2 to 10 swipeable cards, making them ideal for step-by-step guides, feature breakdowns, or product comparisons.

• Card Size: $1080 times 1080$ pixels ($1:1$ square ratio)
• Technical Specs: Max 10 MB per card; formats include JPG or PNG.
• Text Limits: Introductory text up to 155 characters recommended; card headlines capped at 45 characters.

3. Video Ads

Video is one of the most effective ways to capture attention in a text-heavy professional feed. LinkedIn supports multiple orientations to fit how your audience holds their devices.

• Landscape (16:9): $1920 times 1080$ pixels (Min: $640 times 360$)
• Square (1:1): $1920 times 1920$ pixels (Min: $360 times 360$)
• Vertical (4:5): $1080 times 1350$ pixels (Min: $360 times 450$)
• Full Vertical (9:16): $1080 times 1920$ pixels (Min: $360 times 640$)
• Technical Specs: MP4 format, file size ranging from 75 KB to 500 MB, and a duration between 3 seconds and 30 minutes (though 15 to 30 seconds typically yields the highest completion rates).

4. Document Ads

If you are promoting thought leadership assets like whitepapers, annual reports, or comprehensive guides, Document Ads let users flip through a PDF directly inside the feed without navigating away.

• File Types: PDF, DOC, DOCX, PPT, or PPTX
• Max File Size: 100 MB
• Page Count: Up to 300 pages (though 5 to 15 pages usually performs best for engagement).

5. Text Ads

Text ads are simple, budget-friendly pay-per-click (PPC) or cost-per-impression (CPM) units that appear discretely along the top or right-hand rail of the desktop experience.

• Logo Size: $100 times 100$ pixels (JPG or PNG, max 2 MB)
• Text Limits: Headline up to 25 characters; description up to 75 characters.

6. Spotlight and Follower Ads (Dynamic Ads)

Dynamic ads automatically personalize themselves by pulling data (like the user’s profile photo and first name) from their public LinkedIn profile to drive page follows or website traffic.

• Company Logo: $100 times 100$ pixels (JPG or PNG, max 2 MB)
• Optional Background Image (Spotlight Ads): $300 times 250$ pixels
• Text Limits: Headline up to 50 characters; description up to 70 characters.

7. Message and Conversation Ads

Delivered directly to a user’s LinkedIn Messaging (InMail) inbox, these ads act as a direct line of communication for high-intent lead generation or event registrations.

• Desktop Banner (Optional): $300 times 250$ pixels (JPG or PNG, max 2 MB)
• Sender Image: Pulls directly from the designated sender’s personal LinkedIn profile.
• Text Limits: Custom message text up to 1,500–8,000 characters (depending on format), with a call-to-action button limited to 25 characters.

Pro-Tips for Flawless LinkedIn Creatives

• Design for “Sound-Off”: Over half of professionals view feeds and videos with the sound off. Always bake burned-in captions or clear text overlays into your video assets.
• Keep Text Out of Corners: Avoid placing critical text, logos, or faces right on the edges of your image assets, as different screen sizes can trigger minor auto-cropping.
• Prioritize Square or Vertical on Mobile: While landscape is safe for cross-device consistency, square ($1:1$) and vertical ($4:5$) assets capture significantly more vertical screen space in the mobile scroll, driving higher engagement rates.