Getting your LinkedIn ad specs right is essential for campaign success. Nothing derails a well-planned campaign faster than rejected creatives or poorly displayed ads that look stretched, pixelated, or cut off on mobile devices.
This guide covers every LinkedIn ad format's exact specifications—dimensions, file sizes, character limits, and aspect ratios—so you can create ads that display perfectly across all devices and placements.
Single Image Ad Specs
Single image ads are LinkedIn's most versatile format, appearing in the feed as Sponsored Content. They're ideal for driving traffic, generating leads, and building brand awareness—especially when combined with proven linkedin-lead-generation-campaign tactics.
Image Requirements
Specification | Requirement |
Recommended Size | 1200 x 627 pixels |
Aspect Ratio | 1.91:1 (landscape) |
Minimum Width | 400 pixels |
Maximum File Size | 5 MB |
File Formats | JPG, PNG, GIF (static only) |
Text Limits
Element | Character Limit | Best Practice |
Ad Name | 255 characters | Internal use only |
Headline | 200 characters | Keep under 70 for full visibility |
Introductory Text | 600 characters | First 150 characters shown before "see more" |
Description | 300 characters | Direct Sponsored Content only |
Best Practices for Single Image Ads
- Use high-contrast visuals that stand out in a busy feed
- Include minimal text on images—LinkedIn doesn't enforce Facebook's 20% rule, but cleaner images perform better
- Test square images (1080 x 1080) which now display well on mobile and take up more feed real estate
- Ensure your headline is under 70 characters to avoid truncation on desktop
According to LinkedIn's advertising guidelines, images should avoid excessive text overlays for optimal engagement. For more creative inspiration, review these linkedin-advertising-case-studies to see what works.

Carousel Ad Specs
Carousel ads let you showcase multiple images or cards that users swipe through. They're excellent for storytelling, showcasing multiple products, or walking prospects through a process.
Card Requirements
Specification | Requirement |
Image Size | 1080 x 1080 pixels |
Aspect Ratio | 1:1 (square) |
Number of Cards | 2-10 cards |
Maximum File Size | 10 MB per card |
File Formats | JPG, PNG |
Text Limits for Carousel Ads
Element | Character Limit |
Ad Name | 255 characters |
Introductory Text | 255 characters |
Card Headline | 45 characters |
Landing Page URL | Required per card |
Carousel Ad Best Practices
- Use all 10 cards when you have enough quality content—more cards mean more engagement opportunities
- Create visual continuity across cards with consistent colors, fonts, and style
- Tell a sequential story that rewards users for swiping through
- Put your strongest card first as many users won't swipe past the first 2-3 cards
- Include a clear CTA on the final card to drive action after the story
Video Ad Specs
Video ads capture attention and drive engagement, with LinkedIn reporting that members spend 3x more time watching video ads compared to static content. Learn the full strategy behind effective linkedin-video-ad-best-practices to maximize your video performance.
Video Requirements
Specification | Requirement |
Recommended Size | 1920 x 1080 pixels (landscape) |
Aspect Ratios | 16:9, 1:1, or 9:16 (vertical) |
Minimum Resolution | 360 pixels |
Maximum File Size | 200 MB |
Duration | 3 seconds to 30 minutes |
File Formats | MP4 |
Frame Rate | 30 fps recommended |
Audio | AAC or MPEG4 |
Video Text Limits
Element | Character Limit |
Ad Name | 255 characters |
Headline | 200 characters (70 recommended) |
Introductory Text | 600 characters |
Video Ad Best Practices
- Capture attention in the first 3 seconds—most users decide quickly whether to keep watching
- Design for sound-off viewing with captions or text overlays since many users browse on mute
- Keep videos under 30 seconds for awareness campaigns; longer videos work for consideration-stage content
- Use 1:1 or 9:16 aspect ratios for mobile-first campaigns—vertical video takes up more screen space on phones
- Include captions—LinkedIn auto-generates them, but uploading your own SRT file ensures accuracy
Text Ad Specs
Text ads appear in the right rail on desktop and are LinkedIn's most cost-effective format, often delivering the lowest CPC for b2b-linkedin-advertising campaigns.
Image Requirements
Specification | Requirement |
Image Size | 100 x 100 pixels |
Aspect Ratio | 1:1 (square) |
Maximum File Size | 2 MB |
File Formats | JPG, PNG |
Text Limits
Element | Character Limit |
Headline | 25 characters |
Description | 75 characters |
Text Ad Best Practices
- Use a clear, recognizable image—logos or headshots work well at this small size
- Front-load your headline with the most important words
- Include a specific offer or benefit in the description
- Create multiple variations to test different messaging angles
- Target desktop users specifically since text ads don't appear on mobile
Understanding linkedin-cpm-explained can help you budget effectively for these cost-efficient placements.
Message Ad Specs (Sponsored Inmail)
Message ads deliver personalized messages directly to LinkedIn members' inboxes. They achieve open rates averaging 50%, significantly higher than email marketing benchmarks.
Message Requirements
Specification | Requirement |
Message Body | 1,500 characters |
Subject Line | 60 characters |
CTA Button Text | 25 characters |
Banner Image (optional) | 300 x 250 pixels |
Banner File Size | 2 MB maximum |
Message Ad Best Practices
- Personalize using dynamic fields like first name, company, and job title
- Keep messages under 500 characters for optimal engagement—shorter messages feel more personal
- Use a conversational tone as if writing to a colleague
- Include only one CTA—multiple links dilute focus and reduce conversion
- Test subject lines aggressively—they determine whether your message gets opened
Many linkedin-lead-generation-companies rely heavily on Message Ads for their top-performing campaigns.
Document Ad Specs
Document ads let you share PDFs, PowerPoints, and Word documents directly in the feed. Users can view documents without leaving LinkedIn, making them excellent for lead generation with gated content.
Document Requirements
Specification | Requirement |
File Formats | PDF, DOC, DOCX, PPT, PPTX |
Maximum File Size | 100 MB |
Page Limit | Up to 300 pages |
Recommended Pages | 10-15 for engagement |
Text Limits
Element | Character Limit |
Introductory Text | 600 characters |
Headline | 200 characters |
Document Title | Displays from file name |
Document Ad Best Practices
- Design for the preview thumbnail—the first page should be visually compelling
- Use landscape orientation for better in-feed viewing experience
- Keep page count between 5-15 pages for lead magnets—enough value to justify contact info
- Gate strategically—you can require Lead Gen Form completion before viewing
- Include your branding on every page since users may screenshot individual slides
For effective document ad creative, reference linkedin-advertising-templates that have proven performance records.
Conversation Ad Specs
Conversation ads create interactive, choose-your-own-adventure style experiences in LinkedIn messaging. This format is particularly effective when implementing linkedin-retargeting strategies to nurture warm audiences.
Requirements
Specification | Requirement |
Message Text | 500 characters per message |
CTA Buttons | Up to 5 per message |
CTA Button Text | 25 characters each |
Banner Image | 300 x 250 pixels |
Conversation Layers | Up to 5 branches |
Event Ad Specs
Event ads promote LinkedIn Events directly in the feed with a one-click attendance button.
Requirements
Specification | Requirement |
Image Size | 1200 x 627 pixels (from event) |
Introductory Text | 600 characters |
Event Name | Pulled from event page |
Lead Gen Form Specs
Lead Gen Forms attach to most ad formats and pre-populate with member profile data for frictionless conversions. They're a cornerstone of best-linkedin-ads-lead-generation strategies.
Form Limits
Element | Limit |
Form Fields | Up to 12 fields |
Custom Questions | Up to 3 |
Privacy Policy URL | Required |
Thank You Message | 300 characters |
Quick Reference: All LinkedIn Ad Sizes
Ad Format | Image Size | Aspect Ratio | Max File Size |
Single Image | 1200 x 627 px | 1.91:1 | 5 MB |
Carousel | 1080 x 1080 px | 1:1 | 10 MB/card |
Video | 1920 x 1080 px | 16:9, 1:1, 9:16 | 200 MB |
Text Ads | 100 x 100 px | 1:1 | 2 MB |
Message Ads Banner | 300 x 250 px | N/A | 2 MB |
Document Ads | N/A | Landscape preferred | 100 MB |

Frequently Asked Questions
What Is the Best Image Size for LinkedIn Ads?
For single image Sponsored Content, use 1200 x 627 pixels with a 1.91:1 aspect ratio. For carousel ads, use 1080 x 1080 pixels (square). Always use the highest resolution possible within file size limits for crisp display on high-density screens. Check how your costs compare across platforms with this facebook-ads-cost-comparison guide.
What Video Length Performs Best on LinkedIn?
For awareness campaigns, videos under 30 seconds perform best. For consideration-stage content targeting engaged audiences, 1-2 minute videos can work well. LinkedIn allows up to 30 minutes, but engagement drops significantly after the first minute for most campaigns.
Do LinkedIn Ads Have Text Limits on Images?
Unlike Facebook, LinkedIn doesn't enforce a strict text-on-image policy. However, images with less text typically perform better because they look more native to the feed. If you must include text, keep it minimal and ensure high contrast for readability.
What File Formats Does LinkedIn Accept for Video Ads?
LinkedIn accepts MP4 files for video ads. Use H.264 video codec and AAC audio codec for best compatibility. Maximum file size is 200 MB, and videos must be between 3 seconds and 30 minutes long.
How Can I Track Ad Performance Across Different Formats?
Proper tracking setup is essential for measuring linkedin-advertising-roi. Install the linkedin-insight-tag-guide on your website to enable conversion tracking, retargeting, and demographic insights across all ad formats. Many businesses partner with a specialized linkedin-ppc-agency or best-linkedin-ad-agency to manage cross-format optimization and tracking.