The Complete Guide to LinkedIn Ad Sizes and Specs

Running ads on LinkedIn is a powerful way to put your brand in front of decision-makers, professionals, and B2B buyers. However, nothing kills a high-performing campaign faster than a rejected creative or a stretched, pixelated graphic that makes your business look amateur.

Because LinkedIn serves professionals across desktop and mobile environments, getting your dimensions right is critical. This comprehensive guide breaks down the core LinkedIn ad sizes, formats, and specifications you need to design campaigns that look sharp and convert.

1. Single Image Ads (Sponsored Content)

Single image ads live right in the user’s feed. They are versatile, easy to test, and work well for driving website traffic, generating leads, or building brand awareness.

• Landscape (1.91:1): 1200 x 628 pixels (Recommended)
• Square (1:1): 1200 x 1200 pixels (Recommended)
• Vertical (4:5): 720 x 900 pixels (Mobile only)
• File Types: JPG, PNG, or non-animated GIF
• Max File Size: 5 MB
• Copy Limits: Introductory text (up to 150 characters), Headline (up to 70 characters)

Tip: Square (1:1) and vertical (4:5) formats take up more physical space on mobile screens, often yielding higher click-through rates than landscape formats.

2. Carousel Image Ads

Carousel ads let you showcase multiple scrolling cards in a single ad unit. They are ideal for telling a step-by-step brand story, highlighting product features, or presenting a content series.

• Card Aspect Ratio: 1:1 square
• Recommended Image Size: 1080 x 1080 pixels
• Number of Cards: 2 to 10 cards
• File Types: JPG, PNG, or non-animated GIF
• Max File Size: 10 MB per card
• Copy Limits: Introductory text (up to 255 characters), Card headline (up to 45 characters)

3. Video Ads

Video is one of the best ways to capture attention in a text-heavy professional feed. LinkedIn supports multiple aspect ratios depending on how your video was shot and where you want it to appear.

• Landscape (16:9): 1920 x 1080 pixels
• Square (1:1): Up to 1920 x 1920 pixels
• Vertical (4:5): 720 x 900 pixels (Recommended for vertical feed)
• Vertical (9:16): 720 x 1280 to 1080 x 1920 pixels
• File Format: MP4
• File Size: 75 KB to 500 MB
• Duration: 3 seconds to 30 minutes (shorter, punchier videos typically perform best)

4. Document Ads

Document ads allow you to share whitepapers, case studies, or slide decks directly inside the LinkedIn feed without forcing users to leave the platform.

• Accepted Formats: PDF, DOC, DOCX, PPT, PPTX
• Max File Size: 100 MB
• Page Limit: Up to 300 pages (though shorter, digestible guides usually see higher engagement)

5. Text Ads

Text ads are simple, cost-effective right-rail or top-banner ads displayed on desktop views. Because they are compact, they rely heavily on concise copywriting.

• Logo Image Size: 100 x 100 pixels
• File Types: JPG or PNG
• Max File Size: 2 MB
• Copy Limits: Headline (up to 25 characters), Description (up to 75 characters)

6. Dynamic Ads (Spotlight & Follower Ads)

Dynamic ads personalize content automatically using the target user’s profile data (like their name, company, or job title).

• Company Logo: 100 x 100 pixels (JPG or PNG, max 2 MB)
• Spotlight Background Image (Optional): Exactly 300 x 250 pixels
• Copy Limits: Company name (up to 25 chars), Headline (up to 50 chars for Spotlight), Description (up to 70 chars)

7. Sponsored Messaging (Message & Conversation Ads)

These ads deliver targeted messages directly to your prospects’ LinkedIn Inboxes. While the text handles the heavy lifting, you can add visual assets to boost conversions.

• Sender Image: Automatically pulls from the designated sender’s LinkedIn profile
• Desktop Banner Image (Optional): 300 x 250 pixels (JPG or PNG, max 2 MB; desktop only)
• In-Message Image (Optional): 250 x 250 pixels (recommended square format)

Best Practices for LinkedIn Ad Design

1. Design for Mobile First: Over 60% of LinkedIn traffic originates from mobile devices. Vertical (4:5) and square (1:1) ad dimensions take up more screen real estate and prevent your ads from feeling lost.
2. Mind the Safe Zones: Keep crucial text, logos, and focal points away from the very edges of your images and videos. UI overlays (like play buttons, time stamps, and profile markers) can occasionally obscure corners.
3. Keep Text Readable: B2B buyers scroll quickly. Ensure your font sizes are large enough to be read effortlessly on a smartphone screen, and avoid cluttering your graphics with dense paragraphs.
4. Match Your Creative to Your Goal: Use Single Image or Video formats for broad awareness and top-of-funnel reach, Carousels or Documents for educational depth, and Lead Gen forms or Sponsored Messaging to capture intent directly.