Demystifying LinkedIn Ad Sizes: The Ultimate Guide to Perfect Creative Dimensions

When it comes to B2B marketing, LinkedIn is the gold standard. With hundreds of millions of professionals, decision-makers, and thought leaders scrolling through its feeds every day, it offers an unmatched opportunity to target high-value audiences. However, even the most compelling copy and precise targeting will fall flat if your visual assets look pixelated, awkwardly cropped, or out of place.

Adhering to the correct LinkedIn ad sizes is the difference between a campaign that captures attention and one that gets scrolled past in a fraction of a second. This comprehensive guide covers everything you need to know about LinkedIn ad dimensions, aspect ratios, and file requirements to ensure your brand always puts its best foot forward.

Why LinkedIn Ad Sizes Matter

Before diving into the pixel counts, it’s worth understanding why getting your dimensions right is critical:

• Professional Credibility: Blurry, stretched, or cut-off imagery signals a lack of attention to detail—the exact opposite of the polished image most brands want to project.
• Maximized Screen Real Estate: Platforms optimize for specific aspect ratios. Using the right size ensures your ad takes up the maximum allowable space on both desktop and mobile screens.
• Higher Engagement: Ads that fit natively into the user experience naturally yield better click-through rates (CTR) and lower cost-per-click (CPC) rates.

1. Single Image Ads

Single image ads are the bread and butter of LinkedIn advertising. They appear directly in the user’s feed alongside organic posts, making them versatile for brand awareness, lead generation, and website traffic.

• Landscape (Horizontal):
  • Recommended Size: 1200 x 627 pixels
  • Aspect Ratio: 1.91:1
• Square:
  • Recommended Size: 1200 x 1200 pixels
  • Aspect Ratio: 1:1
• Vertical (Portrait):
  • Recommended Size: 628 x 1200 pixels
  • Aspect Ratio: 1:2 (Note: Vertical ads are mobile-only and offer superior screen dominance).
• File Requirements:
  • Max file size: 5 MB
  • File types: JPG, PNG, GIF (non-animated)

2. Carousel Image Ads

Carousel ads allow you to showcase multiple images in a swipeable format. This is ideal for telling a brand story, highlighting a range of products, or breaking down a step-by-step process.

• Recommended Size: 1080 x 1080 pixels per card
• Aspect Ratio: 1:1
• Card Count: 2 to 10 cards per ad
• File Requirements:
  • Max file size: 10 MB per card
  • File types: JPG, PNG

3. Video Ads

Video is one of the most engaging mediums on LinkedIn. Whether you’re sharing customer testimonials, product walkthroughs, or company culture pieces, hitting the right video specifications is non-negotiable.

• Landscape (Horizontal): 1280 x 720 pixels (16:9)
• Square: 1080 x 1080 pixels (1:1)
• Vertical (Portrait): 1080 x 1350 pixels (4:5) or 1080 x 1920 pixels (9:16)
• Length: 3 seconds to 30 minutes (though 15–30 seconds typically performs best for top-of-funnel engagement).
• File Requirements:
  • Max file size: 200 MB
  • File types: MP4
  • Frame rate: 30 fps or lower

4. Message Ads (Sponsored Content in InMail)

Message ads land directly in a user’s LinkedIn messaging inbox, offering a personalized touchpoint. While the primary component is text, they rely heavily on companion banner ads.

• Companion Banner Ad Size: 300 x 250 pixels
• Aspect Ratio: 6:5
• File Requirements:
  • Max file size: 40 KB
  • File types: JPG, GIF (non-animated), PNG
  • Note: Companion banners are desktop-only.

5. Text Ads

Text ads are simple, cost-effective pay-per-click (PPC) or cost-per-impression (CPM) ads that appear on the right-hand rail of the desktop experience. Because of their modest footprint, the image is optional, but highly recommended for catching the eye.

• Logo / Image Size: 100 x 100 pixels
• Aspect Ratio: 1:1
• File Requirements:
  • Max file size: 2 MB
  • File types: JPG, PNG

6. Document Ads

LinkedIn Document Ads allow you to share long-form PDFs, whitepapers, or pitch decks directly in the feed, enabling users to flip through documents without ever leaving the platform.

• Supported File Types: PDF, DOC, DOCX, PPT, PPTX
• Orientation: Portrait or Landscape (Portrait is generally easier to read on mobile feeds).
• Max Page Count: Up to 300 pages (though shorter, punchier guides usually see higher completion rates).

Best Practices for LinkedIn Creatives

Knowing the dimensions is only half the battle. To maximize your ad spend, keep these strategic tips in mind:

1. Design for Mobile First: Over 60% of LinkedIn traffic comes from mobile devices. Vertical and square formats take up more physical space on mobile screens, leading to higher engagement.
2. Keep Text Minimal: While LinkedIn no longer strictly enforces the old “20% text rule” on images, cluttered graphics perform poorly. Let your primary ad copy do the heavy lifting, and use imagery to evoke emotion or highlight a clear product screenshot.
3. Add Subtitles to Videos: Many professionals browse LinkedIn with their sound off while at work or on commute. Always burn open captions or subtitles directly into your video files.
4. Include a Clear Call-to-Action (CTA): Utilize LinkedIn’s built-in button options (