How to Improve Ad Viewability: 5 Proven Ways for Good Visibility and High Revenue

Ad viewability continues to be a hot topic for publishers. As buyers become more discerning and campaign measurement becomes more sophisticated, ensuring that ads are seen has never been more critical. Better viewability doesn't just improve advertiser satisfaction; it also directly correlates with increased competition for your inventory and higher CPMs.

What Is Ad Viewability?

Viewability refers to the percentage of an ad that is visible to a user. The IAB (Interactive Advertising Bureau) defines a viewable impression in their Viewable Ad Impression Measurement Guidelines as:

• Display ads: At least 50% of pixels in view for one continuous second.
• Video ads: At least 50% of pixels in view for two continuous seconds.
• Large formats (e.g. 970x250): 30% of pixels in view for at least one second.

These standards guide programmatic buying, direct campaigns, and brand safety strategies.

Why Viewability Matters

We began improving the viewability of one publisher's ad placements, which initially had a viewability rate of 57%, and there were 6,480 advertisers on the site per month. After two months, the viewability had risen to 73.7%, with 10,203 advertisers on the site. If 60% used to be an acceptable baseline, many publishers are now aiming for 80–90% as a new standard.

Poor viewability not only drives away buyers but also weakens your position in header bidding auctions, impacts your direct sales credibility, and may lead to wasted impressions.

5 Key Factors That Impact Ad Viewability (and How to Fix Them)

1. Creative Weight and Load Speed

Problem: Heavy or poorly coded creatives take too long to load, leading to missed viewability opportunities.

• Enforce file size limits and encourage async loading.
• Use initial lightweight loads with post-load elements.
• Limit the number of third-party tracking pixels.
  
  

1. Creative Weight and Load Speed

Problem: Heavy or poorly coded creatives take too long to load, leading to missed viewability opportunities.

• • Enforce file size limits and encourage async loading.
  • Use initial lightweight loads with post-load elements.
  • Limit the number of third-party tracking pixels.
    
    

2. Page Load Speed

Problem: Slow websites delay ad rendering, often causing below-the-fold ads to never appear in time.

• • • • Use asynchronous tag loading.
      • Minimise third-party scripts.
      • Run performance audits using tools like Google Lighthouse or WebPageTest.

3. Lazy Loading

Problem: Without lazy loading, below-the-fold ads are loaded immediately, hurting performance and potentially being missed.

• • Implement lazy loading to trigger only when an ad is near the viewport (e.g. within 300px).
  • Set smart thresholds and preload offsets.
  • Test loading performance to balance latency and revenue.
    
    

4. Header Bidding Optimisation

Problem: Inefficient bidder setups or slow response times reduce the chance of timely ad rendering.

• • Monitor and adjust bidder timeout settings.
  • Prioritise high-performing demand partners.
  • Consider reducing the number of bidders or shifting to a server-side implementation to speed up auctions.
    
    

5. Ad Refresh Settings

Problem: Refreshing ads too quickly or without viewability logic can lead to wasted impressions.

• • • Use viewability-triggered refresh (e.g. only refresh if ad is >70% in view for 5+ seconds).
    • Avoid time-based refresh alone.
      

Use the Right Tools to Make It Happen

While there are many moving parts in improving viewability, having the right tools makes the process easier. Platforms like Relevant Yield can help publishers:

• Monitor viewability performance by placement, device type, and demand source.
• Run multivariate tests on settings like ad refresh and lazy loading.
• Identify underperforming bidders or creatives using data and AI.

Whether you're adjusting lazy load thresholds, optimising bidder timeouts, or streamlining your ad stack, Relevant Yield supports a data-driven approach to improving viewability. With our Prebid wrapper’s intuitive no-code UI, you can quickly manage and configure setups without relying on developer resources.

Conclusion

High viewability isn’t just about satisfying advertisers—it’s about making every impression count. From smart placement strategies to performance-first site design, even small improvements can yield major gains.

Keep testing, keep optimising, and let your data lead the way. Need help understanding where to start? Get in touch and let’s take a look at your inventory together.