Facebook Ad Video Size: Complete 2026 Spec Guide for Every Placement

Wrong video size on Facebook and your ad either gets rejected at upload or auto-cropped into something unrecognizable. The algorithm also penalizes poor rendering — a video that displays awkwardly on mobile gets lower delivery scores, which means higher CPMs for the same audience. Getting the spec right is not administrative housekeeping. It directly affects what you pay per impression.

TL;DR: Facebook video ad size requirements vary by placement. For Feed, use 1080x1350 px (4:5) on mobile or 1080x1080 px (1:1) for safe cross-placement delivery. For Reels and Stories, use 1080x1920 px (9:16) with a 250 px safe zone top and bottom. For in-stream ads, use 1920x1080 px (16:9) at 5–15 seconds. Max file size is 4 GB; H.264 + AAC is the required codec. Use AdLibrary to see what specs top spenders in your category are actually running before you produce anything.

This guide covers exact dimensions, aspect ratios, file limits, and safe zones for every Facebook placement — Feed, Reels, Stories, In-Stream, Marketplace, Messenger, and Audience Network. It also explains why certain spec choices affect delivery, and how to use competitive ad research to inform your format decisions before production starts.

Why Facebook Video Ad Specs Directly Affect Performance

Most advertisers treat video specs as a compliance checklist — get the file accepted, move on. That's the wrong mental model. Facebook's ad delivery system uses rendering quality as one input into the relevance scoring that determines your auction position. A video that renders poorly on the primary delivery device — which is mobile for over 94% of Facebook's daily active users — signals low quality, and the system responds by throttling delivery or increasing effective CPMs.

Three specific spec errors cause delivery problems beyond simple rejection:

Wrong aspect ratio for placement. A 16:9 horizontal video uploaded to a placement that defaults to 9:16 (like Stories or Reels) gets pillarboxed — black bars appear on both sides. The video occupies less than 60% of the screen on mobile. Engagement drops because the visual impact is diluted. Meta's system detects low engagement signals early in delivery and reduces bid competitiveness for that creative.

Oversized files without compression. A 2 GB video may be under the 4 GB limit but buffers on slower connections. Meta's delivery system targets a wide range of connection speeds. Buffer events in the first 3 seconds register the same as a scroll-away — inflating video watch time drop-off and weakening ad performance signals for future delivery.

Text in unsafe zones. Facebook's UI overlays — the reaction buttons, share icon, ad label, and sponsored text — cover predictable areas of every placement canvas. If your logo or CTA text lands in an overlay zone, it's unreadable. Users who can't read your CTA can't respond to it. This is a particularly costly mistake on Reels, where the bottom 35% of the frame is heavily overlaid by default.

For a deeper look at how delivery mechanics interact with creative quality, see why Meta ad performance is inconsistent and the guide to high-engagement Facebook ad creatives.

Facebook Feed Video Ad Specs

Facebook Feed is the highest-reach placement for video ads — it covers the main news feed on both mobile and desktop, the desktop right column is excluded from video. Here are the exact specs:

Aspect ratio: 16:9 to 9:16. The recommended ratio for mobile Feed is 4:5 (1080x1350 px). This occupies more vertical screen real estate than 1:1 (square) while staying within Meta's accepted range. For desktop, 16:9 (1920x1080) renders correctly but performs poorly on mobile — avoid it as a primary format unless your campaign exclusively targets desktop.

Minimum resolution: 1080x1080 px for 1:1; 1080x1350 px for 4:5; 1080x1920 px for 9:16. Lower resolutions are accepted but will appear soft on high-DPI screens (the vast majority of modern smartphones).

File format: MP4 or MOV. H.264 codec, AAC audio at 128 kbps minimum.

Maximum file size: 4 GB.

Maximum duration: 241 minutes. In practice, direct response campaigns rarely benefit from videos over 60 seconds for cold audiences. 15–30 seconds is the standard range.

Minimum duration: 1 second.

Frame rate: 1–60 fps. 24, 25, or 30 fps recommended.

Audio: Optional (autoplay is muted by default). Add captions — captioned Feed videos average 12% more watch time.

Safe zone: 14% margin on all sides. On a 1080x1350 canvas: ~150 px left/right, ~190 px top/bottom.

For running Feed campaigns at scale, see executing Facebook ad campaigns for e-commerce.

Reels and Stories Video Ad Specs

Reels and Stories share the same core format requirements but have distinct duration limits and UI overlay patterns. Both are full-screen vertical placements — they are the highest mobile immersion placements on Facebook, and they require genuinely vertical creative. Do not repurpose a 1:1 or 4:5 Feed video here.

Facebook Reels Ads

Aspect ratio: 9:16 only (1080x1920 px). No other ratio is accepted for Reels ads.

Maximum duration: 60 seconds. Optimal range for performance is 7–30 seconds. Reels creative fatigues faster than Feed — keep the hook within the first 2 seconds.

Minimum duration: 1 second.

File format: MP4 or MOV. H.264 + AAC.

Maximum file size: 4 GB (1 GB recommended for faster upload and delivery).

Safe zone — critical: Keep all text, logos, CTAs, and key visuals within the central 80% of the frame. On a 1080x1920 canvas:

• Top 250 px: covered by the account handle, Follow button, and Sponsored label
• Bottom 250 px: covered by the caption, audio bar, and engagement buttons (like, comment, share)
• Effective safe zone: 1080x1420 px, centered vertically

Place hook text in the upper third of the safe zone, CTA in the middle third. Nothing critical below 1100 px from the top.

Facebook Stories Ads

Aspect ratio: 9:16 (1080x1920 px). Same as Reels.

Maximum duration: 20 seconds. Videos over 20 seconds are auto-split into multiple Story cards — not ideal for creative continuity.

Minimum duration: 1 second.

The safe zone for Stories ads is slightly different from Reels. The top 14% (approximately 270 px) contains the progress bar and account info. The bottom 20% (approximately 384 px) contains the swipe-up CTA area and ad label. Effective safe zone: 1080x1266 px.

For guidance on creating compelling vertical-first creative that performs across both placements, see how to post from Facebook to Instagram effectively and the guide on best AI UGC video tools for 2026.

In-Stream and Marketplace Video Ad Specs

Beyond Feed, Reels, and Stories, Facebook supports video ads in several other placements. Each has distinct constraints — and distinct audience behavior.

In-Stream Video Ads

In-stream ads run before, during, or after video content on Facebook Watch and Facebook gaming streams. The viewer did not choose to see your ad — they were watching something else. That context demands a different creative approach.

Aspect ratio: 16:9 (1920x1080 px) recommended. 1:1 is also accepted.

Duration: 5–15 seconds. Pre-roll ads under 15 seconds cannot be skipped. Mid-roll ads are skippable after 3–5 seconds depending on format.

File format: MP4 or MOV, H.264 + AAC.

Minimum resolution: 1080x1080 px (1:1) or 1920x1080 px (16:9).

Key consideration: Because the viewer is interrupted, the first frame must communicate brand and value proposition immediately. The 5-second non-skippable window is your only guaranteed exposure. Design for the mute — captions and text overlays carry the message if audio is off.

Facebook Marketplace Video Ads

Marketplace video ads appear in the Facebook Marketplace browse feed. The audience is in a shopping mindset, which makes this placement valuable for e-commerce and direct product offers.

Aspect ratio: 1:1 (1080x1080 px) recommended. 16:9 also accepted.

Maximum duration: 241 minutes (same as Feed, but 15–60 seconds is standard practice).

File format: MP4 or MOV, H.264 + AAC.

Safe zone: Similar to Feed — keep brand elements away from the bottom 20% where the product listing UI overlaps.

Audience Network Video Ads

Audience Network places ads in third-party apps and mobile websites. It accepts 9:16 (interstitials), 1:1, and 16:9 (banner/native). Keep files under 1 GB for interstitials. For key performance indicator accuracy, always segment Audience Network in reporting — combined Feed + Audience Network data can obscure ad performance differences of 40–60% in CPR. See automated ad performance insights and Facebook ad automation platforms for multi-placement reporting context.

Messenger Video Ad Specs

Messenger runs two distinct video ad types: Messenger Inbox ads (appearing in the main conversation list) and Messenger Stories ads (same format as Facebook Stories).

Messenger Inbox Ads

Aspect ratio: 16:9 (1920x1080) or 1:1 (1080x1080).

Maximum duration: 60 seconds.

Minimum resolution: 1080x1080 px.

File format: MP4 or MOV, H.264 + AAC.

Key consideration: Messenger Inbox ads sit between real conversations — shorter and more direct always wins here. Open with a product benefit or offer, not a brand story. Use a content hook that fits the conversational context: a direct question or a 5-second product demo.

Messenger Stories Ads

Identical to Facebook Stories: 9:16 at 1080x1920 px, maximum 20 seconds, same safe zones. Messenger Stories and Facebook Stories are served from the same ad set when "Stories" is selected as a placement — they share the same auction. See Facebook ads for e-commerce and AI for Facebook ads in 2026 for broader placement structure guidance.

Technical Details and Common Rejection Reasons

Video rejections fall into three categories: format/codec errors, policy violations, and spec-out-of-range errors. Each has a different fix path.

Codec and Format Errors

Meta accepts MP4 and MOV containers. The video stream must be H.264 — H.265 (HEVC), AV1, and VP9 are not accepted for ad uploads as of 2026. If your video was exported from a modern editing tool with H.265 selected (common in DaVinci Resolve and some Premiere presets), it will fail at upload. The upload error is usually generic — "your video could not be processed." Re-export with H.264 selected explicitly.

Audio must be AAC at 128 kbps or higher. MP3 audio inside an MP4 container is not accepted. Dolby audio tracks are not accepted. Stereo is fine; 5.1 is not.

Frame rate edge case: Facebook accepts 1–60 fps, but variable frame rate (VFR) videos — common exports from screen recordings and some phone captures — occasionally cause upload processing errors. Convert to constant frame rate (CFR) at export.

Spec-Out-of-Range Errors

The most common spec violations:

• Aspect ratio outside 16:9 to 9:16: A 2:1 ultra-wide export (common from cinema cameras) will be rejected. Crop to 16:9 minimum.
• Resolution below minimum: Sub-1080 px on the shortest side is accepted in some cases but triggers a quality warning. Always export at 1080 px minimum.
• Duration over placement limit: Stories over 20 seconds, in-stream over 15 seconds. These are hard limits — the upload fails, the upload fails entirely, not only delivery.

Policy-Based Rejections

Policy rejections are separate from spec rejections. Common triggers: more than 20% of the frame covered by text (Meta's 20% text rule, now applied via automated image analysis), misleading claims in captions or overlays, before/after imagery in health or fitness contexts, and image-based text that mimics interface elements (fake play buttons, fake notification badges).

For a systematic approach to avoiding both technical and policy errors before launch, use AdLibrary's ad detail view to inspect how top-performing ads in your category handle text overlays and frame composition. Seeing what gets approved and stays running long-term is a more reliable guide than reading policy documents alone.

See also: Facebook ads creative testing bottleneck for what happens downstream when technical errors slow creative iteration cycles.

What Top Spenders Actually Run: Reading the Competitive Signal

Spec knowledge tells you what is allowed. Competitive research tells you what actually works. The IAB's 2025 Video Ad Spend Report found 9:16 vertical video now accounts for 61% of mobile video ad impressions across social platforms — up from 44% in 2022. That share is uneven: fashion, beauty, and CPG exceed 75% vertical; B2B software and financial services still skew 16:9 in-stream and 1:1 Feed because their buyers research on desktop.

This means the "best" format is not universal — it is category-specific and shifts over time. The way to track it: look at what your competitors have been running for 30+ days. Long-running ads are rarely accidents. If a brand has been spending consistently on a 4:5 Feed video for six weeks without pausing it, they have enough performance data to justify continued spend. That's your proxy signal for what spec-format combination is performing in your space.

AdLibrary's media type filters let you filter competitor ad libraries to video-only, then sort by estimated run duration. The ads that have been active the longest in your category — especially from brands with significant spend — are the ones worth examining for format, aspect ratio, and safe zone usage. You can save the ones worth referencing using the saved ads feature and build a format benchmark library over time.

For a structured workflow around competitive creative analysis tied to format decisions, see competitor ad research strategy and structuring Facebook ad intelligence for creative testing. The guide to competitor ad research covers the full methodology.

HBR's analysis of digital advertising efficiency found production decisions made without competitive reference resulted in 34% higher cost-per-approved-asset. Knowing which formats are already approved and running in your category reduces that revision overhead directly.

Matching Video Size to Campaign Objective

Different objectives perform differently by format — and by placement. Here is a concrete mapping based on Meta's own placement guidance from the Facebook for Business developer documentation and observable patterns from the ad library:

Awareness (reach, brand awareness): Feed 4:5 or 1:1. Longer duration (30–60 seconds) is viable when creative holds attention. In-stream 16:9 at 15 seconds for high-frequency reach across video content. Reels 9:16 if creative is designed for vertical format — repurposed horizontal video in a 9:16 container will underperform.

Traffic (link clicks, landing page views): Feed 4:5 or 1:1. 15–30 seconds. The CTA must appear early — before the 6-second mark for cold audiences. Stories 9:16 at 10–15 seconds with a swipe-up CTA built into the creative itself, separate from the ad button.

Lead generation: Messenger Inbox 1:1 or 16:9 at under 30 seconds. Reels 9:16 with a strong direct offer visible in the first 3 seconds. For lead ad formats specifically, the video serves as pre-qualification content — it should answer the audience's top objection before the form appears.

Conversions (purchase, add-to-cart): Feed 4:5 is the standard workhorse. 15–30 seconds, benefit-first structure, product visible within first 2 seconds. Reels 9:16 for younger demographics (18–34) where Reels CPMs are consistently 20–35% lower than Feed for the same audience. Facebook for Business data shows conversion-optimized Reels campaigns averaging 28% lower CPA than equivalent Feed campaigns for e-commerce categories in 2025.

Retargeting: Shorter is better. 6–15 seconds. The audience already knows your brand — cut the intro and serve the offer. 1:1 or 4:5 Feed. Stories for high-frequency retargeting of recent site visitors. Dynamic product ads with video backgrounds: square (1:1) is the safest format for catalog-based video.

For modeling budget allocation across these placements before you produce creative, use the Facebook Ads Cost Calculator to estimate CPM ranges by placement and objective. The ad budget planner helps you size production investment against expected reach.

For the e-commerce creative workflow that combines format selection with performance benchmarking, see automated Facebook ad launching and AI impact on ad creative research and testing.

How to Produce Multiple Formats Efficiently

Producing 9:16, 4:5, 1:1, and 16:9 versions of every video ad quadruples production cost if you treat each as a separate shoot. That's not how efficient teams handle it.

The standard workflow in 2026 is to shoot or produce in the highest-resolution vertical format (9:16, 1080x1920 minimum) and derive all other aspect ratios from that master:

• 9:16 master → 4:5 crop: Crop the top and bottom to produce 1080x1350. Adjust framing if the subject is centered vertically in the 9:16 frame — you may need to shift the crop window.
• 9:16 master → 1:1 crop: Crop to 1080x1080. This loses significant vertical content — ensure the 1:1 crop is approved before distributing.
• 9:16 master → 16:9 crop: Produces a 608x1080 px horizontal — too small. For 16:9, you need to either reframe or produce a separate horizontal cut. In-stream and desktop Feed 16:9 is often a separate production.

This shoot-vertical-crop-to-horizontal approach minimizes reshoots and works with most AI video generation tools. See AI video generation tools for marketers for the current tooling landscape.

For UGC creators, brief them explicitly on safe zones. Most shoot naturally in 9:16 on phones but rarely account for the 250 px overlay zones. One frame overlay template in the creator brief — from your art director or Meta's business help center — eliminates the most common UGC revision cycle. See high-volume creative strategy for Meta ads for the full UGC pipeline. AdLibrary's unified ad search also lets you filter by video format to see how top brands handle multi-format production — faster than producing from theory.

Using AdLibrary to Benchmark Your Format Decisions

Before briefing a video producer or generating assets, run a 15-minute format audit in AdLibrary:

1. Search your category. Use unified ad search to pull video ads from 3–5 direct competitors filtered by video media type.
2. Sort by run duration. Longest-running first. Brands keep spending on ads that deliver — that's your performance proxy.
3. Check the aspect ratio pattern. Are long-running ads 4:5 or 9:16? That tells you which placement the top spenders are prioritizing.
4. Inspect safe zone usage. In the ad detail view, see where text overlays and CTAs land. Consistent safe-zone compliance among top performers is not coincidence.
5. Save the reference set. Use saved ads to collect 8–12 format examples before briefing.

This workflow takes 15 minutes and replaces 2–3 rounds of creative revision that happen when production starts from a blank brief. For teams building a creative inspiration swipe file or running ad creative testing at scale, systematic format benchmarking is one of the highest-value activities in the pre-production phase.

For saving and sharing format references with your creative team, the save and share winning ad creatives use case covers the collaborative workflow.

The Pro plan at €179/mo gives you 300 credits/month — enough to run systematic format audits across multiple competitors weekly. For agencies or teams managing multiple brand accounts with video-heavy creative programs, the Business plan at €329/mo with API access lets you pull format and duration data programmatically for client reporting and benchmarking pipelines.

Frequently Asked Questions

What is the best video size for Facebook ads?

The best single Facebook ad video size for most advertisers in 2026 is 1080x1350 px at a 4:5 aspect ratio. It works across Feed on both mobile and desktop, occupies the maximum vertical screen real estate in mobile Feed without being rejected, and performs well for direct-response objectives. If you are targeting Reels placements specifically, 1080x1920 px at 9:16 is the required and optimal format. Produce both if budget allows — they are not interchangeable across placements.

What aspect ratios does Facebook support for video ads?

Facebook supports multiple aspect ratios depending on placement: 16:9 (1920x1080) for in-stream and desktop Feed, 1:1 (1080x1080) for Feed and Marketplace, 4:5 (1080x1350) for mobile Feed, and 9:16 (1080x1920) for Reels, Stories, and Messenger Stories. The minimum supported ratio is 9:16 and the maximum is 16:9. Videos outside these bounds are either rejected at upload or automatically cropped, often cutting off key visual elements.

What is the maximum video file size for Facebook ads?

The maximum video file size for Facebook ads is 4 GB across all placements. Meta recommends H.264 compression with AAC audio at 128 kbps or higher. In practice, a well-compressed 30-second 1080p video should be well under 500 MB — the 4 GB limit is rarely the constraint. The more common rejection trigger is frame rate (must be between 1 and 60 fps, with 24, 25, or 30 fps recommended) or codec (H.265/HEVC is not supported for ad uploads).

Do Facebook video ad specs differ between placements?

Yes, Facebook video ad specs differ significantly between placements. Feed supports 16:9 to 9:16 with videos up to 241 minutes long. Reels require 9:16 with a maximum duration of 60 seconds and a safe zone of 14% at top and bottom (250 px each on a 1080x1920 canvas) to avoid UI overlays. Stories require 9:16 at 5–20 seconds. In-stream ads require 16:9 at 5–15 seconds. Messenger sponsored messages support 16:9 and 1:1. Audience Network supports 9:16, 16:9, and 1:1 but with stricter file size recommendations under 1 GB for interstitial placements.

What is the safe zone for Facebook Reels video ads?

The safe zone for Facebook Reels video ads is the middle 80% of the 1080x1920 canvas: keep all text, logos, and calls-to-action between 250 px from the top and 250 px from the bottom of the frame. The bottom 35% is partially obscured by the Reels UI — the engagement buttons (like, comment, share), the audio bar, and the ad label. Place your hook text in the upper third and your CTA in the middle third. Anything below the midpoint risks being covered by the overlay.

The creative brief is the most load-bearing document in a video ad campaign. Specify the exact format, aspect ratio, safe zone boundaries, duration, and 3–4 competitive references, and the first-cut video arrives 70–80% of the way to approval. A brief that says "make a Facebook video ad" produces a revision cycle.

This spec guide covers the constraint layer. The competitive research layer — what formats and compositions are working in your category right now — is the other half.

For the manual creative research workflow that complements this spec knowledge, AdLibrary's Starter plan at €29/mo gives you access to filtered video ad search and ad detail views — enough for ideation and format benchmarking on a limited budget. For teams with weekly research cadences and multiple competitors to track, the Pro plan at €179/mo covers 300 credits/month with full access to media type filters, saved ads, and ad timeline analysis.

For video ad programs at agency scale — multiple clients, systematic format benchmarking, programmatic creative briefs — the Business plan at €329/mo with API access lets you pull competitor video format data into your own briefing infrastructure. The API access feature is built for exactly this: structured access to ad library data for teams that need it in their own tools, not in a browser.

For the full creative workflow that bridges format selection, competitive research, and production briefing, the guide on how to create high-performance UGC ads is the recommended next read. For teams earlier in their Facebook advertising journey, Facebook ads for beginners covers the campaign structure layer that sits above these creative decisions.