Master the Feed: The Definitive Guide to LinkedIn Paid Ad Specs

Running campaigns on LinkedIn without checking the technical specifications is a fast track to wasted budget and fuzzy creatives. Because LinkedIn caters to a professional audience operating across everything from ultra-wide desktop monitors to fast-scrolling mobile devices, your ads must adapt seamlessly to multiple formats.

Whether you are launching single-image thought leadership, heavy-hitting video campaigns, or interactive carousels, this comprehensive guide covers the exact dimensions, file limits, and text constraints required to make your campaigns look pristine and perform at their peak.

1. Single Image Ads

Single-image sponsored content is the bread and butter of B2B marketing. It anchors the feed, provides a clear link preview or visual hook, and supports both desktop and mobile placements.

• Landscape (1.91:1):
  • Recommended Size: $1200 times 627$ or $1200 times 628$ pixels
  • Best for: Classic link shares, landscape illustrations, and website traffic campaigns.
• Square (1:1):
  • Recommended Size: $1200 times 1200$ pixels
  • Best for: Maximum feed real estate that renders uniformly across desktop and mobile.
• Vertical / Portrait (4:5):
  • Recommended Size: $720 times 900$ pixels
  • Best for: Mobile-only dominance. It takes up maximum vertical feed space, though it will not display on desktop feeds.

General Requirements:

• File Formats: JPG, PNG, or non-animated GIF.
• Max File Size: 5 MB.
• Text Limits: Introductory text is best kept under 150 characters to prevent truncation (max 600 characters). Headlines should stick to 70 characters (max 200).

2. Video Ads

B2B buyers consume an immense amount of video, but video performance relies heavily on proper encoding. Because a vast majority of users watch LinkedIn videos on mute, burned-in captions or uploaded SRT caption files are essential.

• Landscape (16:9): $1920 times 1080$ pixels
• Square (1:1): Up to $1920 times 1920$ pixels
• Vertical (4:5): $720 times 900$ or $1080 times 1350$ pixels
• Vertical (9:16): Up to $1080 times 1920$ pixels

General Requirements:

• File Format: MP4
• File Size: 75 KB to 500 MB
• Duration: 3 seconds to 30 minutes (though 15 to 30 seconds yields the highest retention for ads).
• Frame Rate: 30 frames per second recommended.

3. Carousel Ads

Carousels let you tell a sequential story, break down a complex framework, or display a multi-product catalog within a single ad unit.

• Card Dimensions: $1080 times 1080$ pixels (1:1 square)
• Card Count: 2 to 10 cards per carousel
• File Formats: JPG, PNG, or non-animated GIF
• Max File Size: 10 MB per card
• Text Limits: Card headlines are capped at 45 characters if linked to a destination URL or Lead Gen Form.

4. Document Ads

If you are promoting high-value gated content—like industry benchmarks, whitepapers, or comprehensive playbooks—Document Ads let users flip through a PDF directly inside the LinkedIn feed without navigating away.

• File Types: PDF, DOC, DOCX, PPT, or PPTX
• Max File Size: 100 MB
• Page Limit: Up to 300 pages (shorter, highly visual guides usually see stronger completion rates).

5. Thought Leader Ads & Direct Sponsored Content

Thought Leader Ads allow you to amplify organic posts published by real executives, founders, or employees.

• The Golden Rule: The underlying asset must follow the standard specifications of whatever format was originally published (whether it’s a text post, single image, or video). Ensure your employee creators don’t use non-standard aspect ratios that break upon sponsorship.

6. Messaging & Dynamic Ads (Spotlight / Follower)

For account-based marketing (ABM) and direct-to-inbox campaigns, LinkedIn offers personalized messaging and right-rail placements:

• Message & Conversation Ads:
  • Text: Up to 1,500 characters for Message Ads (customizable with tokens like first name).
  • Companion Banner: Optional $300 times 250$ pixel desktop banner (JPG/PNG, max 2 MB).
• Spotlight & Follower Ads (Desktop Right-Rail):
  • Company Logo: $100 times 100$ pixels (JPG/PNG, max 2 MB).
  • Spotlight Background Image (Optional): $300 times 250$ pixels.
  • Headline/Description: Keep headlines tight (around 50 characters) to avoid awkward mid-word truncation.

💡 Pro-Tip for Creative Ops: Always design your text elements with a “safe zone” in mind. Keep critical copy, logos, and calls to action away from the extreme edges of your templates to prevent LinkedIn’s UI overlays (like video timecodes or profile icons) from obstructing your message.