LinkedIn Paid Ad Specs: Sizes & Formats Guide

Cracking the Code: The Definitive Guide to LinkedIn Paid Ad Specs

Running campaigns on LinkedIn without checking the technical specifications first is an expensive mistake. Because LinkedIn targets decision-makers, professionals, and B2B buyers, its ad ecosystem has strict formatting parameters. An asset that looks stunning on Instagram or Facebook can easily look cropped, pixelated, or rejected if it misses LinkedIn’s precise dimensions and file size caps.

Whether you are launching single-image sponsored updates, high-intent lead gen forms, or dynamic messaging campaigns, understanding the exact rules of the road is crucial for maximizing your return on ad spend (ROAS).

1. Sponsored Content (Single Image Ads)

Single-image ads are the workhorse of B2B marketing, appearing directly in the professional feed across desktop and mobile.

• Landscape (1.91:1):
  • Recommended Size: $1200 times 628$ pixels
  • Delivery: Desktop and mobile
• Square (1:1):
  • Recommended Size: $1200 times 1200$ pixels
  • Delivery: Desktop and mobile
• Vertical (4:5):
  • Recommended Size: $720 times 900$ pixels
  • Delivery: Mobile only (high engagement for scrollers)
• File Types: JPG, PNG, or GIF (non-animated)
• Max File Size: 5 MB
• Copy Limits: Introductory text (recommended under 150 characters for mobile truncation safety, though up to 600 is technically allowed); Headline (recommended under 70 characters).

2. Video Ads

Motion captures attention quickly in a text-heavy network. LinkedIn supports multiple aspect ratios depending on your creative orientation:

• Landscape (16:9): $1920 times 1080$ pixels
• Square (1:1): Up to $1920 times 1920$ pixels
• Vertical (4:5 / 9:16): $720 times 900$ pixels or $1080 times 1920$ pixels
• File Format: MP4 (H.264 or VP8)
• File Size: 75 KB to 500 MB
• Duration: 3 seconds to 30 minutes (shorter, punchier formats generally win on conversion rates).
• Frame Rate: 30 FPS or lower

3. Carousel Ads

Carousels allow you to tell a sequential story, showcase a product suite, or present a step-by-step framework.

• Number of Cards: 2 to 10 cards
• Image Size: $1080 times 1080$ pixels (1:1 aspect ratio)
• File Types: JPG or PNG
• Max File Size: 10 MB per card
• Card Headline: Up to 45 characters (for Sponsored Content)

4. Document Ads

If you are promoting thought leadership assets, whitepapers, case studies, or slide decks directly in the feed, Document Ads let users swipe through PDFs or presentations natively.

• File Types: PDF, PPT, PPTX, DOC, or DOCX
• Max File Size: 100 MB
• Page Limit: Up to 300 pages

5. Messaging Ads & Conversation Ads

Directly dropping value into a prospect’s LinkedIn inbox yields high response rates when personalized.

• Message Text: Up to 1,500 characters (Conversation ads can support branching structures with longer text pools).
• Call to Action (CTA): Up to 20–25 characters
• Optional Desktop Banner: $300 times 250$ pixels (JPG or PNG, max 2 MB)

6. Text Ads & Dynamic Ads (Spotlight / Follower)

These native right-rail placements are budget-friendly options for lead gen, brand awareness, and growing your company page follower base.

• Text Ad Logo: $100 times 100$ pixels (JPG or PNG, max 2 MB)
• Text Limits: Headline max 25 characters; Description max 75 characters
• Spotlight Ads: Require a $100 times 100$ pixel logo and support an optional $300 times 250$ pixel background image.

Quick Best Practices for Success

1. Design for Mobile First: Over 60% of LinkedIn traffic occurs on mobile devices. Utilizing vertical ($4:5$) single-image dimensions or square formats ensures your visual asset fills real estate effectively.
2. Mind the Safe Zones: Keep crucial text and logos away from the absolute edges of your creative assets to avoid getting clipped by UI overlays (like video time stamps or profile tags).
3. Keep Copy Concise: Professional audiences skim. Clear value propositions combined with a frictionless Lead Gen Form (pre-filled with accurate LinkedIn profile data) will consistently outperform long-winded text.