Facebook vs TikTok vs YouTube: Where to Run AI Video Ads

"Where should I run my video ads?" is the wrong first question. The right first question is: "Who am I trying to reach, what action do I want them to take, and how much can I pay per action?"

The answer to that question points you to the right platform — or, more likely, the right combination of platforms. Each of the three major video ad channels (Facebook/Instagram, TikTok, YouTube) has distinct strengths, cost structures, and audience behaviors that make it ideal for specific campaign objectives.

This guide gives you the data to make that decision without guessing.

Platform Overview at a Glance

Facebook & Instagram: The Precision Targeting Workhorse

Who to Reach

Facebook and Instagram offer the broadest demographic coverage and the most sophisticated targeting options. The combined user base spans every age group, though the platform skews increasingly toward 25-54 for purchasing behavior.

Strongest audience segments: Parents, homeowners, mid-career professionals, online shoppers with established purchase histories. Facebook's pixel data and Advantage+ campaigns make it the strongest platform for retargeting and lookalike audiences.

Cost Structure

Facebook ad costs have risen steadily since 2020 but remain competitive for direct-response campaigns. The auction system rewards high-relevance ads with lower CPMs, which means creative quality directly impacts cost efficiency.

• Average CPM: $8-$14 (US market)
• Average cost per purchase (ecommerce): $15-$45
• Minimum viable daily budget: $20-$50 per ad set

Format Best Practices

• Reels (9:16) are now the highest-reach format. If you are only producing one format, make it a Reel.
• Keep it under 30 seconds. The platform rewards completion rate, and shorter videos complete at higher rates.
• Design for sound-off first. 40% of Facebook viewers watch without sound. Text overlays and visual storytelling must carry the message independently.
• Use the first frame as a thumbnail. Unlike YouTube, Facebook auto-plays from frame one. That first frame is your hook.

Algorithm Insights

Facebook's algorithm optimizes for the action you tell it to optimize for — but it needs data to learn. The learning phase requires roughly 50 optimization events per week per ad set. Below that threshold, performance is unstable.

Key takeaway: Consolidate ad sets rather than fragmenting budget. Fewer ad sets with more budget each will outperform many ad sets with thin budgets.

TikTok: The Creative-First Discovery Engine

Who to Reach

TikTok's audience has aged up significantly since 2022. While Gen Z remains the core, 35% of US TikTok users are now over 30, and the platform's purchase intent metrics are climbing across all age groups.

Strongest audience segments: Trend-responsive consumers, impulse buyers, beauty and fashion enthusiasts, and audiences who discover products through content rather than search.

Cost Structure

TikTok offers the lowest entry costs of the three platforms, making it ideal for testing creative concepts before scaling on Facebook or YouTube.

• Average CPM: $5-$10 (US market)
• Average cost per purchase (ecommerce): $10-$35
• Minimum viable daily budget: $20 per ad group

Format Best Practices

• Vertical only (9:16). Horizontal video on TikTok is functionally invisible.
• 9-15 seconds is the sweet spot. TikTok's algorithm heavily rewards completion rate, and shorter videos complete more often.
• Native aesthetic outperforms polished production. Ads that look like organic TikTok content see 2-3x higher engagement than ads that look like ads.
• Sound is essential. 90% of TikTok is consumed with sound on. Audio (voiceover, trending sounds, music) is not optional.
• Use Spark Ads when possible. Boosting organic-style content through Spark Ads inherits social proof and typically delivers 30-40% lower CPA.

Algorithm Insights

TikTok's algorithm prioritizes content freshness more aggressively than any other platform. A new ad with strong early engagement will get distribution regardless of account history. This makes TikTok the most meritocratic platform for new advertisers.

Key takeaway: Creative quality matters more than targeting precision on TikTok. Invest 80% of your effort in the creative and 20% in the targeting.

YouTube: The Intent-Driven Conversion Platform

Who to Reach

YouTube is where people go to learn, research, and decide. This makes it fundamentally different from Facebook and TikTok, where users are in discovery mode. On YouTube, viewers often have purchase intent before they see your ad.

Strongest audience segments: B2B decision-makers, high-consideration purchasers, education seekers, and audiences in the research phase of the buying journey.

Cost Structure

YouTube's cost structure varies dramatically by format. Shorts are cheap; skippable in-stream ads are moderate; non-skippable ads are expensive.

• Average CPM (Shorts): $4-$8
• Average CPM (In-Stream): $10-$20
• Average cost per view (skippable): $0.01-$0.05
• Minimum viable daily budget: $10-$30

Format Best Practices

• YouTube Shorts (9:16, under 60s) compete directly with TikTok Reels at lower costs. If you are producing TikTok content, cross-post to Shorts.
• Skippable in-stream ads (16:9, 30-60s) are the flagship format. The first 5 seconds determine whether you pay — you only get charged after 30 seconds or a click.
• Hook within 5 seconds or lose the viewer. On skippable ads, the skip button appears at 5 seconds. Your hook must be compelling enough to earn continued attention.
• Sound-on design is mandatory. 95% of YouTube viewers have sound enabled. Use voiceover, not just text overlays.

Algorithm Insights

YouTube values watch time and click-through above all else. Ads with high view-through rates get lower CPMs because YouTube wants to show ads that do not drive viewers away from the platform.

Key takeaway: YouTube rewards ads that feel like content. Educational, story-driven, and demonstration-style ads outperform hard-sell approaches.

Decision Matrix: Where to Run Based on Your Goals

By Campaign Objective

By Monthly Ad Budget

By Industry

Cross-Platform Creative Strategy

The most efficient approach is not creating unique content for each platform. It is creating a modular content system that adapts:

1. Start with a 30-second master script using the frameworks in our video ad script writing guide.
2. Produce the 30-second version first for Facebook and YouTube In-Stream.
3. Cut a 15-second version for TikTok and Instagram Reels.
4. Create a 6-second bumper from the strongest hook for YouTube bumper ads.
5. Adjust the aesthetic — more polished for YouTube, more native/raw for TikTok.

AI video tools make this multi-format production practical. What used to require a week of editing now takes an afternoon. Explore platform-ready video creation at AdConvert's solutions page.

Common Platform Migration Mistakes

When expanding from one platform to multiple, teams make predictable errors that waste their first 30 days of spend on the new platform:

Mistake #1: Applying Facebook targeting logic to TikTok. Facebook rewards narrow, interest-based targeting. TikTok's algorithm performs better with broader audiences because it optimizes on creative engagement, not profile data. Start broad on TikTok and let the algorithm find your audience through content performance.

Mistake #2: Running YouTube creative on TikTok. A polished, 16:9, narrator-led YouTube ad reformatted to 9:16 will look and feel foreign on TikTok. Native TikTok ads should feel like they were made by a creator, not a production studio. The reverse also applies — raw TikTok content on YouTube pre-roll feels out of place.

Mistake #3: Splitting budget evenly across platforms on day one. Allocate 60-70% to your proven platform and 30-40% to the new one. This protects your baseline performance while giving the new platform enough budget to learn. Equalize only after the new platform proves profitable.

Mistake #4: Ignoring platform-specific attribution windows. Facebook defaults to 7-day click, 1-day view. TikTok uses 7-day click, 1-day view but weighs view-through differently. YouTube often requires 30-day attribution to capture the full conversion path. Compare performance using consistent windows, or your data will mislead you.

Frequently Asked Questions

Next steps: Build your first batch of platform-optimized video ads with AdConvert, or avoid the most common pitfalls with our guide to 5 AI video ad mistakes that burn your budget.