The Complete Guide to LinkedIn Ad Sizes and Specifications

Navigating LinkedIn advertising specs can sometimes feel like trying to hit a moving target. Because LinkedIn is the premier platform for B2B marketing, networking, and professional branding, your campaigns need to look polished, crisp, and native to the feed. Blurry graphics or awkwardly cropped text instantly hurt your brand credibility.

This comprehensive guide breaks down the exact dimensions, file types, and text limits for LinkedIn’s most popular ad formats.

1. Single Image Ads (Sponsored Content)

Single image ads appear directly in the user’s feed, making them one of the most common and versatile ways to drive traffic, brand awareness, or leads.

• File Types: JPG, PNG, or GIF (non-animated)
• Max File Size: 5 MB

Aspect Ratios & Dimensions:

• Landscape (1.91:1): 1200 x 628 pixels (Delivers on both desktop and mobile)
• Square (1:1): 1200 x 1200 pixels (Recommended for flexible multi-device delivery)
• Vertical (4:5): 720 x 900 pixels (Optimized for mobile-only feeds; yields high engagement)

Pro Tip for Copywriting: While LinkedIn allows up to 150 characters of introductory text before truncation on mobile devices, try to keep your hook punchy. Keep your headline to 70 characters or less so it doesn’t get cut off.

2. Carousel Image Ads

Carousels let you tell a sequential story, highlight multiple product features, or break down a step-by-step process across swipeable cards.

• Number of Cards: 2 to 10 cards
• Image Size: 1080 x 1080 pixels (1:1 aspect ratio)
• File Types: JPG or PNG
• Max File Size: 10 MB per card
• Headline Limit: 45 characters max (for destination URL ads)
• Introductory Text: 255 characters max (recommended under 150 to avoid early mobile truncation)

3. Video Ads

Video is a powerful medium for building brand authority and demonstrating complex software or services. LinkedIn supports several orientations depending on your production style.

• File Format: MP4
• File Size: 75 KB to 500 MB
• Duration: 3 seconds to 30 minutes (though shorter, punchier videos perform best)

Recommended Video Dimensions:

• Landscape (16:9): 1920 x 1080 pixels
• Square (1:1): Up to 1920 x 1920 pixels
• Vertical (4:5): 720 x 900 pixels (Highly recommended for mobile feed attention)
• Vertical (9:16): 720 x 1280 to 1080 x 1920 pixels

4. Text Ads & Spotlight Ads (Dynamic Ads)

Dynamic ads personalize themselves using the viewer’s profile data (like their job title, company name, or profile photo) and show up on the right rail of the desktop interface.

Text Ads:

• Image/Logo: 100 x 100 pixels (JPG or PNG, max 2 MB)
• Headline: 25 characters max
• Description: 75 characters max

Spotlight Ads:

• Company Logo: 100 x 100 pixels (JPG or PNG, max 2 MB)
• Custom Background Image (Optional): 300 x 250 pixels
• Headline: 50 characters max
• Description: 70 characters max
• Company Name: 25 characters max

5. Document Ads (Content Ads)

Document ads allow you to gate or share long-form thought-leadership content—like whitepapers, ebooks, or case studies—directly inside the LinkedIn feed without requiring users to leave the app.

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

Summary Checklist Before You Launch

1. Double-check mobile view: Over 60% of LinkedIn traffic happens on mobile devices. Prioritize square (1:1) or vertical (4:5) formats for feed ads.
2. Respect the text limits: Keep key values and hooks within the safe character limits to prevent abrupt cutting or ellipses (...).
3. Export clean assets: Stick strictly to recommended pixel dimensions to prevent LinkedIn’s compression algorithm from making your sharp graphics look pixelated.