Facebook Ad Sizes: Complete Specs Guide for 2026

Wrong ad sizes silently kill performance. Meta auto-crops your creative when dimensions don't match the placement, cutting off headlines, hiding CTAs, and adding black bars that scream "this is an ad." Over 80% of Facebook users access exclusively on mobile, which means vertical and square formats aren't optional — they're baseline requirements.

This guide covers every Meta ad dimension that matters in 2026 — Feed, Stories, Reels, Carousel, In-Stream, Marketplace, and more. Five core formats handle 90%+ of placements. Master those first, then optimize for edge cases.

Quick Reference: Core Ad Sizes

Most campaigns only need two formats: 1:1 (1080x1080) for Feed placements and 9:16 (1080x1920) for Stories and Reels. These cover the majority of effective Meta advertising.

Feed Ad Specifications

1:1 Square Format (Primary)

1080x1080 pixels at 1:1 ratio is the default for Feed ads. It maximizes mobile screen space, avoids cropping issues across placements, and achieves 15% higher CTR compared to landscape formats in mobile Feed. File limits: 30MB for images (JPG/PNG), 4GB for video (MP4/MOV). Higher resolutions rarely improve performance but slow load times — 1080px is the sweet spot.

4:5 Vertical Alternative

1080x1350 pixels gives you 20% more mobile screen space than 1:1, which can boost engagement for single-image hero ads. But there's a critical limitation: never use 4:5 in carousel ads. Meta crops carousel cards to 1:1, cutting off the top and bottom of your creative. Default to 1:1 for Feed, use 4:5 selectively for standalone creatives.

Stories and Reels Specifications

Stories and Reels require full-screen 9:16 vertical creative (1080x1920 pixels). Using anything else creates black bars and tanks performance. Native 9:16 drives 41% higher engagement vs. cropped formats. Video duration sweet spot is under 15 seconds — fast cuts maintain attention. Front-load your value proposition.

Safe Zones (Critical)

Not all 1080x1920 pixels are visible. Meta overlays UI elements that cover your creative. Keep the top 14% clear (~250px) — the profile icon and account name cover this area. Keep the bottom 35% clear (~672px) — CTA buttons, captions, and swipe-up overlays sit here. That leaves the center 51% (pixels 250-1248) as your guaranteed viewable area. All essential text, logos, and key visuals must live in this zone.

Other Placement Specifications

In-Stream Video: 1920x1080 (16:9) or 1080x1080 (1:1). These appear during video content users are already watching. Keep ads 5-15 seconds, clear branding in first 3 seconds. 16:9 feels more native in this placement.

Marketplace & Search Results: 1080x1080 (1:1). Users browse with high purchase intent, so ads should look like organic listings — clean product imagery, clear pricing, minimal text overlay.

Right Column (Desktop): 1080x1080 (1:1). Meta standardized this from the old 1.91:1 ratio, making it easy to repurpose Feed creatives. Still effective for retargeting desktop users.

Audience Network: 1:1 square (1080x1080) for native and banner ads, 9:16 vertical (1080x1920) for full-screen interstitials. Messenger: 1080x1080 (1:1), same as Feed specs.

Creative Production Tips

Build an asset library, not one-off ads. Create master creatives at the highest resolution needed, then generate all required formats from there. Most campaigns only need 1:1 and 9:16 assets to cover primary placements. Add 16:9 for In-Stream video if that's part of your strategy. Tools like Canva, Adobe Express, and Figma handle multi-format resizing in minutes.

Text overlay: The old 20% text rule is gone, but the principle holds — less text performs better. Meta's algorithm may reduce delivery for text-heavy creatives. Keep image headlines to 5-7 words max and let your ad copy field handle the details.

Sound-off design: The majority of Feed video plays without sound. Add captions or text overlays for key messages. Watch your ad muted first — if the message is unclear, add visual text. Stories and Reels have a higher sound-on rate, but captions are still essential for accessibility.

Common Sizing Mistakes

Using one size for all placements. Advantage+ Placements will auto-crop a single creative across formats, but the results are usually poor — important elements get cut, black bars appear, and engagement drops. Create format-specific creative for at least Feed (1:1) and Stories/Reels (9:16).

Ignoring safe zones. Placing logos in the top 250px of Stories or CTA text in the bottom 672px means UI overlays hide your content. Use safe zone templates in your design tool and preview on an actual mobile device before launch.

Over-compressing files. Aggressive compression saves file size but causes visible pixelation. Balance at 1080px resolution with JPEG quality 80-90% and video bitrate of 5-10 Mbps. Keep images under 5MB and video under 100MB for fast mobile loading.

Wrong aspect ratio for carousels. Using 4:5 vertical images in carousel ads guarantees cropping — Meta forces carousel cards to 1:1. Always use 1080x1080 exclusively for carousels.

Format Selection by Objective

For e-commerce, use 1:1 Feed for product showcase, 9:16 Stories for lifestyle context, and 1:1 carousels for multi-product browsing. For B2B SaaS, 1:1 Feed works best for case studies and testimonials, 9:16 for short product demos. For local businesses, 1:1 Feed for offers and location info, 9:16 Stories for behind-the-scenes content.

Bottom Line

Ad sizing directly impacts CTR, CPC, and CPM. Properly sized creatives get higher relevance scores, which means lower auction costs and better delivery. The essentials: use 1:1 (1080x1080) for Feed placements — it's the most versatile format. Use 9:16 (1080x1920) for Stories and Reels — it's the only format that works full-screen. Respect safe zones on vertical. Keep files optimized for mobile loading.

Start with those two formats and build a reusable asset library. Add 16:9 for In-Stream if needed. That covers 90%+ of effective Meta advertising. Everything else is edge-case optimization — worth doing eventually, but not where your attention should start.