LinkedIn ad specs are notoriously specific — and getting them wrong means your B2B creative looks amateurish in front of exactly the decision-makers you're trying to impress.

This guide covers every LinkedIn ad format with exact dimensions, file requirements, and character limits. Updated for 2026.

Why LinkedIn Specs Matter More Than Other Platforms

LinkedIn's audience is different. Your targets are scrolling between job updates, industry news, and thought leadership content. An ad that's blurry, cropped, or text-overloaded signals low quality — and in B2B, perception is everything.

LinkedIn is also stricter about specs than Meta. Oversized files get rejected. Wrong aspect ratios get cropped in ways that break your layout. Character limits are firm.

Get this right.

Single Image Ads (Sponsored Content)

The most common LinkedIn ad format. Appears in the desktop and mobile feed like an organic post.

Image specs:

Recommended size: 1200 x 627px (1.91:1 landscape)
Also works: 1200 x 1200px (1:1 square)
Minimum size: 400 x 400px
File types: JPG, PNG, GIF (non-animated)
Max file size: 5MB

Character limits:

Introductory text: 150 characters (600 max, but truncated at ~150 on mobile)
Headline: 70 characters (200 max)
Description: 100 characters (shown in some placements)
CTA button: Predefined options (Learn More, Apply Now, Download, etc.)

Best practice: Lead with your value prop in the first 150 characters of the intro text. Most users won't click "see more." Use the headline to reinforce the CTA, not repeat the intro.

Carousel Ads

Multiple cards that users swipe through. Effective for storytelling, product walkthroughs, and feature showcases.

Specs per card:

Recommended size: 1080 x 1080px (1:1 square) — required for all cards
All cards must be the same aspect ratio
File types: JPG, PNG
Max file size: 10MB per card
Min cards: 2
Max cards: 10

Character limits per card:

Introductory text: 255 characters
Card headline: 45 characters
Card CTA: Optional per card; last card requires a destination URL

Best practice: Hook in card 1, deliver value in cards 2–4, close with a CTA in the final card. Don't front-load features — lead with a problem statement or bold claim.

Video Ads

Video in the LinkedIn feed. Higher production expectations than TikTok or Instagram — your audience is at work.

Specs:

Recommended size: 1920 x 1080px (16:9 landscape) or 1080 x 1080px (1:1)
Also supported: 1080 x 1920px (9:16 vertical, mobile only)
File types: MP4
Max file size: 200MB
Duration: 3 seconds to 30 minutes
Recommended duration: 15–30 seconds for performance campaigns
Minimum resolution: 360p
Aspect ratios: 1:2.4 to 2.4:1 (any within this range)

Character limits:

Introductory text: 150 characters (600 max)
Headline: 70 characters

Best practice: LinkedIn video autoplay is silent by default. Use captions. Open with a visual hook or on-screen text in the first 3 seconds — don't rely on audio to deliver your hook.

Document Ads

Promoted documents — PDFs, presentations, whitepapers — directly in the feed. Strong for lead gen in professional content contexts.

Specs:

File type: PDF, DOC, DOCX, PPT, PPTX
Max file size: 100MB
Max pages: 300

Character limits:

Introductory text: 255 characters
Headline: 70 characters

Best practice: Gate with Lead Gen Form for highest conversion. Include enough visible preview pages that readers see genuine value before hitting a form.

Message Ads (Sponsored Messaging)

Delivered directly to LinkedIn inboxes. High open rates when targeted well; ignored when they feel spammy.

Specs:

Message body: Up to 500 characters (short = higher open completion)
Subject line: Up to 60 characters
Banner image (optional): 300 x 250px (JPG, PNG, max 2MB)
CTA button text: Up to 25 characters
Footer text: Required legal/opt-out line

Best practice: Write like a human, not a sales robot. One specific ask per message. Personalization tokens (first name, company name) lift response rates. Don't pitch a demo in the opening line.

Conversation Ads

Interactive message format with multiple CTA buttons, allowing branching paths (learn more, see case study, book a call).

Specs:

Message body per card: Up to 500 characters
CTA buttons per card: Up to 5
Button text: Up to 25 characters each
Banner image: 300 x 250px (JPG, PNG, max 2MB)

Best practice: Give genuinely useful options — not just "yes I want to buy" paths. Let users self-select intent level. Works well for top-funnel content distribution.

Dynamic Ads

Personalized ads that pull in the viewer's LinkedIn profile photo, name, or company name. Appear in the right rail on desktop.

Follower Ads — drive Company Page follows Spotlight Ads — link to a landing page Content Ads — promote a download with Lead Gen Form

Specs:

Logo image: 100 x 100px minimum (JPG, PNG)
Headline: Up to 50 characters
Description: Up to 70 characters
CTA: Up to 18 characters

Best practice: Personalization is the feature here. Keep copy short — the dynamic element (the user's photo and name) does the heavy lifting. Too much text fights against itself.

Text Ads

Small right-rail ads on desktop. Lowest CPM on LinkedIn; best used for pure brand awareness or retargeting with simple CTAs.

Specs:

Headline: Up to 25 characters
Description: Up to 75 characters
Image: 100 x 100px (JPG, PNG, max 2MB) — optional
Destination URL: Required

Best practice: Text ads are tiny. One clear message: what you do + who it's for. Don't try to tell a story — there's no room.

Quick Reference: LinkedIn Ad Specs

| Format | Image Size | Max File Size | Intro Text | Headline | |--------|-----------|---------------|------------|---------| | Single Image | 1200 x 627px | 5MB | 150 chars | 70 chars | | Carousel (per card) | 1080 x 1080px | 10MB | 255 chars | 45 chars | | Video | 1920 x 1080px | 200MB | 150 chars | 70 chars | | Document | N/A | 100MB | 255 chars | 70 chars | | Message Ad | 300 x 250px (banner) | 2MB | 500 chars | 60 chars | | Dynamic | 100 x 100px (logo) | N/A | 70 chars | 50 chars | | Text Ad | 100 x 100px | 2MB | 75 chars | 25 chars |

Best LinkedIn Ad Sizes to Start With

If you're new to LinkedIn ads or setting up a campaign quickly:

Single Image 1200 x 627px — Works everywhere, looks professional, easy to produce
Carousel 1080 x 1080px per card — Highest engagement for B2B storytelling
Video 16:9 landscape with captions — Stands out in feed, best for brand awareness

The 1:1 square format is increasingly popular because it performs well on both desktop and mobile feeds. If you can only produce one size, make it square.

Generate LinkedIn-Ready Ad Creative Automatically

Resizing and exporting creative for every LinkedIn format by hand is a time sink — especially when you're managing multiple campaigns.

AdsCreator generates LinkedIn-optimized ad creative automatically. Paste your website URL and the AI extracts your brand colors, fonts, and key messages, then produces on-spec creative for every format — no Photoshop required.

Create LinkedIn ad creative in seconds →

Browse Ad Examples

Looking for inspiration? Browse real ad examples by industry and platform:

Key Takeaways

Default to 1200 x 627px for Single Image — it's the native LinkedIn landscape ratio
Use 1:1 square for carousels — consistency across all cards is required
Captions are mandatory for video — autoplay is silent; you'll lose viewers without them
Keep intro text under 150 characters — anything longer gets cut off on mobile
Message Ads work if they sound human — personalized, one ask, no hard sell in the opener