When it comes to Facebook video ads, the technical details matter. A lot. Generally, you’ll be working with vertical (4:5, 9:16) or square (1:1) aspect ratios, using MP4 or MOV files under 4GB, and aiming for a minimum resolution of 1080x1080 pixels. Video length is where it gets tricky—it can range from just 15 seconds for In-Stream ads to much longer formats in the Feed.
Your Quick Reference Guide To Facebook Video Ad Specs
Getting your Facebook video ad specifications right isn't just a box-ticking exercise; it's the very foundation of a successful campaign. If you nail these technical requirements, your creative will look sharp and professional across every placement, from the immersive, full-screen experience of Reels to the familiar scroll of the Feed.
Get them wrong, and you're looking at awkward cropping, fuzzy video quality, or even outright ad rejection from Meta. This guide is your go-to cheat sheet. Use it as a final check before you export to make sure your dimensions, file size, and video length are all optimized for peak performance.
The infographic below gives you a quick visual summary of the core differences between the top three placements—Feed, Stories, and Reels—and the aspect ratios they favor.
As you can tell, the days of a one-size-fits-all video are long gone. To drive real engagement, you absolutely have to tailor your creative to each placement's native format. For a more detailed breakdown of this, check out our complete guide on the ideal size for Facebook ads.
Facebook Video Ad Specifications Cheat Sheet (2026)
To make things even simpler, I’ve put together a quick-reference table. It covers the most critical technical specs for the top Facebook and Instagram video ad placements. Bookmark this page and use it whenever you're about to hit 'export'.
| Placement | Aspect Ratio | Recommended Resolution (Pixels) | Max Video Length | Max File Size |
|---|---|---|---|---|
| Feed | 1:1 or 4:5 | 1080 x 1080 | 240 minutes | 4GB |
| Stories | 9:16 | 1080 x 1920 | 60 seconds | 4GB |
| Reels | 9:16 | 1080 x 1920 | 90 seconds | 4GB |
| In-Stream | 16:9 or 1:1 | 1080 x 1080 | 5–15 seconds | 4GB |
Think of this table as your starting point. While these are the core, must-follow requirements, there's more to the story. In the sections that follow, we'll dive into the specific nuances for each placement, covering everything from recommended codecs and creative best practices to strategies for squeezing every last drop of performance out of your videos.
Universal Technical Specs and Creative Best Practices
Before you start tweaking your creative for specific placements like Reels or Stories, you have to get the universal technical requirements right. Think of these as the foundation for every single Facebook video ad you'll ever run. Getting them wrong means you risk upload errors, ugly compression artifacts, or poor playback that can kill a campaign before it even gets off the ground.
While your video's dimensions will change depending on the placement, these core file settings are your non-negotiables. Nail these first, and you're halfway there.
Core File and Compression Settings
When you're ready to export, your best bets for file containers are .MP4 and .MOV. These are the formats Meta's systems handle most reliably, giving you a great balance of quality and compatibility. Inside that file, make sure your video is compressed with the H.264 codec—it's the gold standard for web video for a reason.
For your audio, stick to AAC compression with a bitrate of at least 128 kbps and a sample rate of 44.1 kHz. And always, always export in Stereo. Mono audio can sound really flat and amateurish, which you'll definitely notice in those rare moments a user actually has their sound on.
Pro Tip: Lock in your frame rate. A variable or fluctuating frame rate is a recipe for stuttering and other weird playback glitches. A steady 30 frames per second (fps) is a solid choice for smooth, professional-looking video.
Creative Best Practices for a Mobile World
Beyond the tech specs, a few creative ground rules apply almost everywhere on Facebook. In a world of fast-scrolling on mobile devices, these practices can make or break your ad's performance. If you're weighing the pros and cons, our guide on whether advertising on Facebook is still a good bet offers some great perspective.
Here are the three rules I build every video ad around:
- Design for Sound-Off. The overwhelming majority of people watch videos on Facebook without sound. Your message needs to land visually, so use big, clear text overlays or burn-in captions. Never assume someone will hear your voiceover.
- Hook Them in Three Seconds. You have a tiny, fleeting moment to stop the scroll. Make sure your brand, your product, or your most eye-catching shot appears within the first 3 seconds. No exceptions.
- Use Captions. Meta itself recommends captions on all video ads. Not only does this make your content accessible, but it's proven to boost view time and message recall for all those silent viewers.
Once you've mastered these universal rules, both technical and creative, you've built a solid foundation. From here, you can start adapting your content for specific placements, confident that your core video is already primed for performance. To see how these principles come to life, check out our guide on https://www.adstellar.ai/blog/facebook-create-video.
Mastering Vertical Video for Stories and Reels
If you're still treating vertical video as an afterthought, you're missing the point. It’s the undisputed king for grabbing undivided attention on mobile, especially in immersive, full-screen placements like Facebook and Instagram Stories and Reels. These formats are designed to make users feel like they're part of the action, and your ads have to fit in perfectly to stand a chance.
The only aspect ratio that matters here is 9:16. It’s what fills the entire screen and creates that seamless experience. To keep your visuals looking sharp and professional, you absolutely have to aim for a resolution of 1080x1920 pixels. Anything less looks blurry, instantly telling a user your ad doesn't belong.
Key Specifications for Stories and Reels
While Stories and Reels both lean on the 9:16 vertical format, they have small but critical differences in their technical specs, mainly around video length. Getting these details right is the key to optimizing your creative for each spot.
Facebook & Instagram Stories Ads:
- Video Length: You can go up to 60 seconds.
- Best Practice: People tap through Stories at lightning speed. Your job is to hook them immediately. Get your core message across in the first 15 seconds, because Meta will chop your video into 15-second "cards" anyway.
- Interactive Elements: Don't just show a video; make it interactive. Polls, quizzes, and sticker taps are your best friends for stopping the scroll and boosting engagement.
Facebook & Instagram Reels Ads:
- Video Length: You get a bit more breathing room here, up to 90 seconds.
- Best Practice: Reels are all about quick, entertaining content. Just because you have 90 seconds doesn't mean you should use it. Shorter, punchier videos almost always perform better.
- Audio: Sound is a massive part of the Reels experience. Yes, you should still design for sound-off, but using trending audio can give your ad a huge boost in feeling native and improving performance.
The Undeniable Performance Impact of Vertical Video
Getting the vertical specs right isn't just about making things look pretty; it directly hits your campaign’s bottom line. The data is clear: full-screen, mobile-native formats deliver better results. For instance, Reels ads that use the full 9:16 aspect ratio can see a 35% higher click-through rate (CTR). Similarly, vertical videos with sound on have been shown to get a 12% lift in conversion rates—a jump that can seriously lower your customer acquisition costs.
A critical pro-tip: always respect Meta's "safe zones" for these placements. Don't put any crucial text, logos, or calls-to-action in the top and bottom 15% of your video (that's about 250 pixels on each end). These areas get covered up by the platform's own interface, like the profile name or the swipe-up button.
Sharing content effectively between these two powerhouse platforms can also make your life a lot easier. If you're looking to cross-post, our guide on how to share from Facebook to Instagram has some great, practical tips. By following these placement-specific Facebook video ad specifications, you’re making sure your creative not only looks great but works harder to drive real results for your business.
Mastering Feed and In-Stream Video Ads
While Stories and Reels get a lot of buzz for their immersive vertical format, don't sleep on the classic Facebook Feed. It’s still where users spend a huge chunk of their time, making it a critical placement for any advertiser. Nailing the specific facebook video ad specifications for the Feed and its close cousin, In-Stream, is non-negotiable for a successful campaign.
Unlike the rigid 9:16 of vertical placements, the Feed gives you a bit more breathing room. It primarily revolves around two key aspect ratios: 1:1 (square) and 4:5 (vertical). The one you choose can absolutely make a difference in how your ad performs.
Feed Video Ad Specifications
For the Feed, your video creative needs to blend in seamlessly with the native scrolling experience. Nothing screams "I'm an ad!" louder than an awkwardly cropped video, and that's a surefire way to kill engagement.
- Aspect Ratio: Your main choices are 1:1 or 4:5. The 4:5 format is a real winner here, as it takes up more vertical screen real estate on mobile and can help you grab more attention.
- Recommended Resolution: For a 1:1 square video, stick with 1080x1080 pixels. For a 4:5 vertical video, the sweet spot is 1080x1350 pixels.
- Video Length: You have a massive runway here, from 1 second all the way up to 240 minutes. But let’s be real—shorter videos around 15-30 seconds almost always work better.
- Max File Size: The limit is a very generous 4GB.
I've found that the 4:5 aspect ratio consistently delivers top-tier performance for mobile-only Feed campaigns. It gives your ad a commanding presence without forcing someone to turn their phone, striking that perfect balance between visibility and user experience. Getting these details right is crucial, and you can dive deeper into how different ad spots work by checking out various placements in advertising.
In-Stream Video Ad Specifications
In-Stream ads are a completely different animal. These are the short ads that pop up before, during, or after other video content on Facebook Watch. You have a captive audience, but their patience is razor-thin.
Because In-Stream ads interrupt what a viewer chose to watch, your message has to be quick, direct, and valuable. Brevity isn't just a suggestion here; it's a hard requirement.
The specs for In-Stream ads reflect this need for speed and are much stricter than what you find for the Feed.
Key In-Stream Requirements:
- Aspect Ratio: A more traditional 16:9 (landscape) or a 1:1 (square) format is what you'll want to use.
- Recommended Resolution: You should aim for at least 1080x1080 pixels.
- Video Length: This is the most critical spec of all. Your ad must be between 5 and 15 seconds long. There's no wiggle room on this one.
- Sound: Unlike most other placements, sound is often on by default since people are already watching a video. Make sure your audio is clean, crisp, and adds to the experience rather than detracting from it.
Since In-Stream ads catch people who are already in a video-watching mindset, they can be incredibly effective for both brand awareness and direct response. To really level up your campaigns, think about how you can re-engage these viewers through tactics like remarketing with Facebook, often using video formats tailored specifically for these highly engaged audiences. By matching your creative to the right Feed or In-Stream specs, you're setting your video up to look professional and perform at its absolute best.
How Video Length Impacts Ad Performance
When it comes to your Facebook video ads, the duration is one of the most powerful levers you can pull. It directly influences your campaign results. While Meta lets you upload some seriously long videos, the hard truth is that shorter, punchier ads almost always win. The length of your ad shouldn't just be about filling the maximum time allowed; it needs to be a strategic choice driven by the placement and your specific goal.
The real key is matching your video’s length to how people behave in that exact spot on the platform. A user mindlessly scrolling their Feed is in a totally different headspace than someone watching Reels or a video they deliberately chose to watch. If you don't respect their context and attention span, you're just asking to get skipped.
The Sweet Spot for Conversions and Retention
For most campaign objectives, the data consistently points to a "golden window" for video ad length. Videos in the 15-30 second range often hit that perfect sweet spot—they're long enough to tell a compelling story but short enough to keep viewers from swiping away.
We've seen it time and again in performance analysis: this is where conversion rates tend to peak. You can even see completion rates hit as high as 65%. But if you're making a video for the super fast-paced environment of the Feed, you need to go even shorter. Aim for 5-15 seconds, tops. For a deeper dive into how these metrics all tie together, check out our guide to Facebook advertising reporting.
Matching Length to Placement and Objective
The ideal video length is definitely not a one-size-fits-all deal. It changes dramatically based on where your ad will show up and what you’re trying to achieve.
Awareness Campaigns (Top of Funnel): Your goal here is to grab attention and build brand recall, so short and snappy is the only way to go. A 5-15 second video is perfect for the Feed or Reels. Focus on a killer visual hook in the first three seconds. Just showing your logo early on can boost brand recall by over 20%.
Consideration Campaigns (Middle of Funnel): At this stage, you have a little more room to explain your value proposition. A video between 15-30 seconds works great for showing off a product feature, explaining a key benefit, or running a quick tutorial. This length is a solid choice for Carousel video ads or more detailed Feed ads.
Conversion Campaigns (Bottom of Funnel): It might seem counterintuitive, but shorter is still usually better here, too. A punchy 15-30 second ad can create a powerful sense of urgency. Save your longer videos (60+ seconds) for retargeting highly engaged audiences who have already shown interest and are actively looking for more in-depth information.
It's critical to remember the law of diminishing returns. Engagement can absolutely fall off a cliff for longer videos. For instance, videos over an hour long see engagement plummet to less than 0.46%, making them a horribly inefficient choice for almost any advertising goal.
The First Three Seconds Rule
No matter how long your video is, the first three seconds are everything. Seriously. This is where you either win or lose the battle for your audience's attention. Your opening shot has to be visually arresting, spark curiosity, or immediately present the problem your product is about to solve.
Since the vast majority of views happen in muted autoplay environments, your message must be crystal clear without any sound. The winning formula is a strong visual hook combined with concise on-screen text or captions. One study found that using captions with fewer than 10 words can significantly boost engagement. To see more of these powerful video stats, you can read the full findings about video ad performance. At the end of the day, mastering video length is a core part of your overall facebook video ad specifications strategy.
Why Mobile-First Video Specs Are Non-Negotiable
Knowing the technical specs for a Facebook video ad is one thing. Truly understanding why they matter is what separates an average campaign from a great one. The reason is simple and can’t be ignored: the overwhelming majority of people on Facebook are scrolling on their phones. If you’re not building your ads for that experience, you're intentionally serving a second-rate ad to most of your audience.
Treating mobile-first design as a priority isn't just a trend—it's the bedrock of effective advertising on the platform today. When you create for mobile, you’re not just shrinking a video down. You're crafting an experience that feels completely native to the user's environment, which is the key to stopping the scroll and actually holding someone's attention.
The Business Case for Vertical Video
Those vertical formats you see everywhere, like 9:16 for Stories and Reels or 4:5 for the Feed, aren't just arbitrary rules. They’re specifically designed to take up as much screen real estate as possible on a smartphone. A video that fills the screen is far more immersive and commands way more attention than a tiny landscape video sandwiched between black bars. That extra visibility has a direct line to better business results.
Think about it: a video made with a 4:5 aspect ratio simply dominates more of the mobile Feed than a traditional 16:9 widescreen video. That simple change can be the difference between a potential customer scrolling right past your ad and stopping to see what you have to say. It’s all about meeting users where they are, in the format they expect.
The core principle is this: adapt your creative to the user's environment, don't force the user to adapt to your creative. An ad that feels natural and non-disruptive is inherently more persuasive.
Connecting Specs to Performance Metrics
Following mobile-first specs isn't just about making things look pretty; it has a direct and measurable impact on your key performance indicators (KPIs). Meta's algorithm is built to reward advertisers who deliver a good user experience. When you upload a video that’s perfectly optimized for its placement, you're sending a strong signal to the platform that your content is high-quality, which can earn you some serious algorithmic love.
The numbers don't lie. Way back in 2018, Meta shared that a whopping 75% of all video views on its platform were happening on mobile, and that figure has only climbed since. More recent data shows that vertical videos with audio can pull a 12% higher conversion rate than their square or landscape counterparts. Even more specific to Reels, ads using the proper mobile format can see a 35% higher click-through rate (CTR). You can dig into more of these powerful Facebook ad statistics to see the full picture.
This data makes it crystal clear: getting your facebook video ad specifications right is a direct path to a more efficient campaign. By creating and testing mobile-first creative that’s perfectly matched to the spec, you can unlock:
- Lower Cost-Per-Acquisition (CPA): When your ads are more engaging and your conversion rates are higher, you simply pay less to get each new customer.
- Higher Return on Ad Spend (ROAS): Better results from more efficient spending naturally pump up the return you see on your investment.
- Greater Scalability: When your ads are performing well, Meta's algorithm is much more likely to show them to a bigger audience, helping you scale your campaigns much more effectively.
Common Questions About Facebook Video Ad Specs
Even with a detailed guide in hand, you'll probably still run into some specific head-scratchers. It happens to everyone. This section is all about getting you quick, no-nonsense answers to the questions we hear from advertisers all the time, helping you fix issues and get your ads running smoothly.
What Is the Best Video Format for Facebook Ads?
The short answer? MP4. It's the undisputed champion for Facebook video ads. It gives you that perfect sweet spot of great video quality and a file size that won't make you want to pull your hair out. Plus, Meta's systems are built to handle it flawlessly.
While you can use MOV files—and they generally work just fine—MP4 is the industry standard for a reason. Its compression is more efficient, making it the go-to for web use. Just make sure you’re using the H.264 video codec and AAC audio compression inside that MP4 container. That's the winning combination.
Can I Use the Same Video for All Placements?
Technically, yes. But you absolutely, positively should not. Honestly, it's one of the biggest and most expensive mistakes you can make. Imagine your beautiful landscape (16:9) ad getting squished into a tiny, awkward box in a vertical Stories placement. Or your tall 9:16 vertical video getting its head and feet chopped off in the Feed. It just doesn't work.
Always—and I mean always—create different video versions for your key placements. At a bare minimum, you need a 9:16 video for Stories and Reels, and a 4:5 or 1:1 video for the Feed. This is non-negotiable if you want your ad to look like it belongs there and not scream "I'm a lazy advertiser!"
Why Was My Video Ad Rejected for Quality?
Nothing's more frustrating than an ad rejection, but when it's for "quality," it usually comes down to a few technical slip-ups. Before you start pulling your hair out, run through this checklist:
- Low Resolution: Is your video width less than 1080 pixels? Anything smaller will look blurry and get flagged almost immediately. Aim for at least 1080p.
- Wrong Aspect Ratio: Trying to shoehorn a video into a placement it wasn't made for (like putting a 16:9 video in a Reels ad slot) is a common cause for rejection.
- Over-Compression: If you crushed your file size down too much, your video is probably a pixelated mess full of compression artifacts. You need to find a healthy balance with your bitrate to keep the quality up.
- Black Bars (Pillarboxing/Letterboxing): This is a huge no-no. Adding black bars to force a video to fit a certain aspect ratio is a rookie mistake that Meta's review system catches easily and almost always rejects.
How Do I Make My Video Ad File Size Smaller?
So your video is a behemoth that blew past the 4GB limit. Don't worry, you can shrink it without turning it into a pixelated mess. The most effective lever you can pull is the bitrate, which is just the amount of data used for each second of video.
Lowering the bitrate will directly shrink your file size. You could also trim the video's length or export it at a slightly lower resolution (but don't dip below that 1080p minimum). For most ads, using a variable bitrate (VBR) setting is a smart move—it saves space on simple scenes and allocates more data to complex, action-packed moments to preserve quality where it counts.
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