Getting your LinkedIn lead generation ads rejected for specification violations wastes time and delays campaigns. This guide provides every technical spec you need to create compliant LinkedIn Lead Gen ads in 2026.
Bookmark this page as your go-to reference for image sizes, video requirements, character limits, and Lead Gen Form specifications.
LinkedIn Lead Gen Forms work with multiple ad formats. Each format has specific creative requirements.
According to LinkedIn's official specifications and 2026 spec updates:
| Element | Specification |
|---|---|
| Image Size | 1200 x 627 pixels (recommended) |
| Aspect Ratio | 1.91:1 |
| File Type | JPG or PNG |
| Max File Size | 5 MB |
| Headline | 70 characters recommended (200 max) |
| Introductory Text | 150 characters recommended (600 max) |
| Description | 100 characters (optional) |
Design Tips:
Carousel ads allow multiple images or cards, each leading to the same Lead Gen Form:
| Element | Specification |
|---|---|
| Card Image Size | 1080 x 1080 pixels |
| Aspect Ratio | 1:1 (square) |
| File Type | JPG or PNG |
| Max File Size | 10 MB per card |
| Number of Cards | 2-10 cards |
| Headline per Card | 45 characters recommended |
| Introductory Text | 150 characters recommended (255 max) |
Design Tips:
Video ads paired with Lead Gen Forms drive strong engagement:
| Element | Specification |
|---|---|
| Resolution | 360p to 1080p |
| Aspect Ratio | 16:9 (landscape), 1:1 (square), 9:16 (vertical) |
| File Type | MP4 |
| Min File Size | 75 KB |
| Max File Size | 200 MB |
| Duration | 3 seconds to 30 minutes |
| Recommended Duration | 15-30 seconds for Lead Gen |
| Frame Rate | 30 fps max |
| Audio | AAC or MPEG4 audio codec |
According to 2026 performance benchmarks, video ads with AI-generated subtitles achieve 80%+ completion rates and 0.82-1.6% CTR.
Design Tips:
Document ads (carousel PDFs) consistently deliver strong CPL performance:
| Element | Specification |
|---|---|
| File Type | PDF, DOC, DOCX, PPT, PPTX |
| Max File Size | 100 MB |
| Max Pages | 300 pages (10 recommended) |
| Recommended Size | 1080 x 1080 pixels per page |
| Title | 70 characters max |
| Introductory Text | 150 characters recommended |
According to 2026 ad format performance data, Document Ads achieve $38-82 CPL, making them the most cost-efficient lead gen format.
The form itself has specific field limits and options:
| Element | Specification |
|---|---|
| Form Name | 256 characters max (internal only) |
| Offer Headline | 60 characters max |
| Offer Detail | 160 characters max (70 recommended) |
| Privacy Policy URL | Required |
| Thank You Message | 300 characters max |
| CTA Button Text | Submit, Sign Up, Subscribe, Request Demo, Learn More, Get Quote, Apply Now, Download, Register |
LinkedIn offers three categories of pre-fillable fields:
Contact Information:
Work Information:
Education:
Custom Questions:
According to lead form completion analysis, form length directly impacts completion rates:
| Number of Fields | Typical Completion Rate |
|---|---|
| 3-4 fields | 25-30% |
| 5-6 fields | 18-23% |
| 7+ fields | 10-15% |
Industry benchmarks for 2026 show that top performers achieve 18%+ Lead Gen Form completion rates by:
| Element | Recommended | Maximum |
|---|---|---|
| Ad headline | 70 | 200 |
| Introductory text | 150 | 600 |
| Description | 100 | 300 |
| Form offer headline | 40 | 60 |
| Form offer detail | 70 | 160 |
| Thank you message | 200 | 300 |
| Custom question | 100 | 300 |
Note: Recommended lengths ensure text displays fully without truncation on both desktop and mobile.
| Requirement | Specification |
|---|---|
| Formats | JPG, PNG, GIF (static) |
| Color Space | sRGB |
| Resolution | 72 DPI minimum |
| Quality | High resolution recommended for retina displays |
| Requirement | Specification |
|---|---|
| Format | MP4 |
| Codec | H.264 |
| Audio | AAC or MPEG4 |
| Bitrate | No specific minimum; balance quality and file size |
| Requirement | Specification |
|---|---|
| Formats | PDF, DOC, DOCX, PPT, PPTX |
| Orientation | Portrait recommended for mobile |
| Font Embedding | Embed all fonts for consistent display |
1. Image Too Small Using images under 1200 x 627 pixels causes blurry display. Always use recommended dimensions.
2. Text Truncation Headlines exceeding 70 characters get cut off on mobile. Preview before publishing.
3. Video Orientation Mismatch Landscape videos waste space on mobile feeds. Test 1:1 or 9:16 for mobile-heavy audiences.
4. Missing Privacy Policy Lead Gen Forms require a valid privacy policy URL. Ads won't publish without it.
5. Too Many Form Fields Every additional field reduces completion rates. Collect only what you need.
The recommended size is 1200 x 627 pixels with a 1.91:1 aspect ratio for single image ads. For carousel ads, use 1080 x 1080 pixels (1:1 square). These dimensions ensure crisp display on both desktop and mobile without cropping.
Aim for 3-4 fields maximum to achieve completion rates above 25%. Each additional field reduces completions by approximately 5-10%. Only request information essential for lead qualification and immediate follow-up.
Keep videos between 15-30 seconds for Lead Gen objectives. While LinkedIn allows up to 30 minutes, shorter videos maintain attention and drive higher form completion rates. Include your key message and CTA within the first 10 seconds.
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