The Complete Guide to LinkedIn Paid Ad Specs: Dimensions, Limits, and Creative Rules

Precision is everything in B2B marketing. Unlike consumer platforms where visual novelty can mask a blurry crop or a poorly formatted layout, LinkedIn is a professional ecosystem. If your creative asset has an awkward text truncation or a pixelated logo, decision-makers notice immediately—and your conversion rates suffer.

Navigating LinkedIn’s technical requirements can feel like threading a needle. This complete, up-to-date breakdown covers specs, dimensions, and character limits across every major LinkedIn ad format.

1. Single Image Ads (Sponsored Content)

The workhorse of B2B lead generation. Single image ads appear natively in the professional feed, blending high-impact visuals with direct response copy.

• Aspect Ratios & Recommended Sizes:
  • Square (1:1): $1200 times 1200$ pixels (Safest bet for cross-device visibility)
  • Landscape (1.91:1): $1200 times 628$ pixels
  • Vertical (4:5): $720 times 900$ pixels (Maximizes mobile screen real estate)
• File Requirements: JPG, PNG, or non-animated GIF; maximum file size of 5 MB.
• Copy & Character Limits:
  • Introductory Text: 150 characters recommended (technically allows up to 600, but anything past 150 risks truncation behind a “see more” link).
  • Headline: 70 characters recommended to avoid cutoff (hard limit at 200).
  • Description (LAN only): 70 characters.

2. Video Ads

Video is unmatched for demonstrating SaaS products, breaking down complex enterprise concepts, or sharing customer testimonials.

• Aspect Ratios & Recommended Resolutions:
  • Landscape (16:9): $1920 times 1080$ pixels
  • Square (1:1): $1080 times 1080$ pixels
  • Vertical (4:5): $1080 times 1350$ pixels
  • Vertical (9:16): $1080 times 1920$ pixels
• Technical Parameters:
  • File Format: MP4
  • File Size: 75 KB to 500 MB
  • Duration: 3 seconds to 30 minutes (Pro tip: High-converting B2B performance ads generally sit between 15 and 30 seconds).
  • Frame Rate: Under 30 FPS
• Copy & Character Limits: Same as Single Image Ads (150-character intro text recommended, 70-character headline).

3. Carousel Ads

Carousels allow you to tell a sequential story, break down a multi-step framework, or showcase a product feature grid using swipeable cards.

• Card Specifications:
  • Card Count: 2 to 10 cards
  • Dimensions: $1080 times 1080$ pixels (1:1 aspect ratio strictly required for cards)
  • File Formats & Size: JPG or PNG; up to 10 MB per card
• Copy & Character Limits:
  • Card Headline: 45 characters maximum
  • Introductory Text: 255 characters maximum

4. Document Ads (Thought Leadership / Content Downloads)

Document ads let users read multi-page PDFs, research reports, or slide decks directly inside the LinkedIn feed without navigating away to a landing page.

• File Requirements:
  • Formats: PDF, DOC, DOCX, PPT, or PPTX
  • File Size: Up to 100 MB
  • Page Limit: Up to 300 pages (Shorter slide decks of 5–15 pages typically perform best).
• Copy & Character Limits: Intro text capped cleanly at 150 characters recommended; headline at 70 characters.

5. Message Ads & Conversation Ads

Delivered directly to a target professional’s LinkedIn Messaging inbox, these formats bypass the traditional feed to yield high open rates.

• Message Ads:
  • Message Text: Up to 1,500 characters
  • Subject Line: 60 characters
  • CTA Button Text: 20 characters
  • Optional Desktop Banner: $300 times 250$ pixels (JPG/PNG, under 2 MB)
• Conversation Ads (Interactive Choose-Your-Own-Path):
  • Message Text: Up to 8,000 characters
  • Custom Footer / Terms: Up to 20,000 characters
  • CTA Button Text: 25 characters each (up to 5 buttons per step)
  • Optional Desktop Banner: $300 times 250$ pixels (JPG/PNG, under 2 MB)

6. Text Ads & Dynamic Ads (Right-Rail Formats)

These minimalist, desktop-heavy units live on the right-hand sidebar of LinkedIn and operate on a pay-per-click (PPC) or cost-per-impression (CPM) model.

• Text Ads:
  • Logo Image: $100 times 100$ pixels (JPG or PNG, max 2 MB)
  • Headline: 25 characters
  • Description: 75 characters
• Spotlight / Follower Ads (Dynamic):
  • Company Logo: $100 times 100$ pixels (JPG/PNG, max 2 MB)
  • Optional Background Image: $300 times 250$ pixels
  • Headline: 50 characters
  • Description: 70 characters
  • CTA Button: 18 characters

💡 Pro-Tip for Campaign Success: Always front-load your value proposition. Because LinkedIn automatically truncates lengthy text blocks with ellipses, keeping your core hook within the 150-character intro text and 70-character headline thresholds ensures your message lands instantly—regardless of whether your audience views it on a desktop monitor or a mobile screen.