Let's talk YouTube Ads, specifically the simplistic question: what are the ideal video length and file sizes? So often we see explainers (like the one our own Sarah Vlietstra wrote) about YouTube Video Ad Types, but rarely do we see a practical walkthrough of recommended video length and ad sizes. That is here! So bookmark this page, and feel free to refer back to it often: 

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1. Recommended YouTube Video Ad Lengths

YouTube ads should be short, engaging, and to the point. The ideal length depends on the ad format and campaign objective:

- Skippable In-Stream Ads (Best for Sales & Brand Awareness)

• Length: 15-45 seconds (sweet spot: 30 seconds)
• Why? Viewers can skip after 5 seconds, so the hook and branding must be strong upfront.
• Suggested Structure:
  
  • 0-5 sec: Hook + problem/solution.
  • 6-15 sec: Show product benefits, visuals, testimonials.
  • 16-30 sec: Reinforce the message + Call to Action (CTA).

- Non-Skippable In-Stream Ads (Best for Retargeting)

• Ideal Length: 10-15 seconds (Google policy length allows for up to 20 seconds max) (cannot be skipped, so concise messaging is key)
• Why? Keeps viewer engagement high without forcing them to watch too long.

- YouTube Shorts Ads (Best for Mobile & Impulse Engagement)

• Ideal Length: 6-15 seconds (Google policy allows for up to 3 mins in length)
• Why? Short-form content works well for quick promotions, impulse purchases, and brand recall.

- Bumper Ads (Best for Awareness & Retargeting)

• Length: 6 seconds (fixed)
• Why? Non-skippable, great for fast brand reinforcement with a single focused message.

- In-Feed Video Ads (Best for Organic Engagement & YouTube Search)

• Length: 45-90 seconds
• Why? These ads appear as recommendations in YouTube search and work better for engaged viewers.

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2. Recommended File Formats & File Sizes

Every advertiser should follow YouTube’s optimal video specs to ensure high quality and smooth delivery.

- File Formats (Recommended by YouTube)

• MP4 (Best Choice – high-quality and widely supported).
• MOV (Apple devices, high-quality but larger file size).
• AVI, WebM, MKV (supported but not as optimized for ad delivery).

- File Size

• Recommended: Under 250MB for smooth ad delivery.
• Maximum Allowed: 128GB (but too large for ads).

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- Resolution & Aspect Ratio

- Bitrate & Frame Rate

• Bitrate: 8 Mbps (1080p), 16 Mbps (4K) (for MP4 files).
• Frame Rate: 30fps or 60fps (avoid lower frame rates for smooth playback).

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💡 Recommendations Summary for YouTube Ad Video Length and File Sizes

✅ Best Video Lengths:

• Primary Skippable Ads: 30 sec (max 45 sec).
• Non-Skippable / Bumper Ads: 6-15 sec.
• YouTube Shorts: 6-15 sec (vertical).
• In-Feed Ads: 45-90 sec.

✅ Best File Format: MP4 (1920x1080 resolution, under 250MB).

✅ Best Aspect Ratios:

• 16:9 for regular ads.
• 9:16 for YouTube Shorts.

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So there you have it, we'll keep this updated as things change, in the meantime we hope it is helpful for you!

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