Mobile Ad Viewability: Standards and Best Practices

The CMO stopped me mid-presentation. "Wait. You're telling me half our ads were never actually seen?"

I pulled up the viewability report. 47% of our display impressions had loaded below the fold. Users scrolled past before they rendered. We'd paid for 2 million impressions that month. Nearly a million of them might as well have been invisible.

That meeting changed how I think about every impression we buy. Viewability isn't a nice-to-have metric—it's the difference between advertising and throwing money into a void.

Viewability Standards

MRC Standard Definition

The Media Rating Council (MRC) defines a viewable impression as:

• Display ads: 50% of pixels in view for 1+ continuous second
• Video ads: 50% of pixels in view for 2+ continuous seconds
• Large ads (242,500+ pixels): 30% of pixels in view

Why Viewability Matters

• Wasted spend: Non-viewable impressions have zero impact
• Brand safety: Viewability issues often correlate with quality issues
• Performance: Viewable ads convert better
• Benchmarking: Enables fair comparison across publishers

Factors Affecting Viewability

Ad Placement

• Above the fold: Higher viewability
• In-content: Variable based on engagement
• Below the fold: Lower viewability
• Sticky/anchored: Very high viewability

Ad Format

• Interstitials: Near 100% viewability
• Native in-feed: 60-80% viewability
• Standard banners: 40-60% viewability

User Behavior

• Scroll speed affects time-in-view
• Session length impacts total viewable time
• App switching can interrupt viewability

Measuring Viewability

Verification Vendors

Third-party measurement ensures objective viewability data:

• IAS (Integral Ad Science)
• DoubleVerify
• Moat (Oracle)
• Pixalate

SDK-Based Measurement

Mobile viewability requires SDK integration for accurate measurement—JavaScript-based methods don't work reliably in apps.

"If you're not measuring viewability with a verified SDK solution, you're likely overestimating actual ad exposure by 20-40%."

Optimizing for Viewability

For Advertisers

• Set viewability thresholds in programmatic buys
• Pay premium for guaranteed viewability
• Exclude low-viewability placements
• Use viewable CPM (vCPM) pricing

For Publishers

• Optimize ad placement for visibility
• Implement lazy loading thoughtfully
• Reduce ad clutter that hurts viewability
• Monitor and improve low-viewability placements

Viewability is table stakes for serious advertisers. Make it a core metric in your reporting, and you'll make better decisions about where to invest your ad budget.