When it comes to digital advertising, size really does matter. The 336×280 Large Rectangle has quietly become one of the most effective display ad formats for boosting engagement and maximizing click-through rates. It’s big enough to grab attention, but not so intrusive that it disrupts the browsing experience.
If you’ve ever scrolled through a website and paused to read a well-placed banner under a headline or at the end of an article, chances are you’ve seen this format in action. The 336×280 isn’t flashy—it’s simply strategic.
In this guide, you’ll see why this ad format stands out, where to place it for the best performance, and how to use it to meaningfully increase user engagement.
What Is the 336×280 Banner Size?
The 336×280 ad displays at:
- Width: 336 pixels
- Height: 280 pixels
- Aspect ratio: ~1.2:1
Google classifies this format as the “Large Rectangle” because it provides more content space than the standard 300×250 medium rectangle. This extra room allows for larger fonts, clearer product images, and a more distinct Call-to-Action (CTA).
336×280 vs. 300×250 — Which Performs Better?
Both sizes are top-performing rectangle formats, but they excel in slightly different ways.
- 300×250 (Medium Rectangle): The “universal” soldier. It fits everywhere, including mobile sidebars.
- 336×280 (Large Rectangle): The “high-impact” specialist. Because it is slightly wider and taller, it commands more visual weight.
When to Choose 336×280:
Select this size when you are targeting Desktop or Tablet users and want a larger visual footprint for your creative assets without feeling like a pop-up.
Where 336×280 Ads Perform Best
1. In-Content / Mid-Article
This is often the highest-performing placement for this size. Users are already focused on the content, and the ad blends naturally into the reading flow. Because it is wider than the standard 300px ad, it breaks up the text more effectively, drawing the eye.
2. End of Article
When a user finishes reading, they are looking for “what’s next.” A 336×280 banner here is perfect for lead capture offers, product recommendations, or newsletter sign-ups.
3. Mobile vs. Desktop Strategy
The 336×280 is primarily a Desktop and Tablet format.
Note: While it can display on modern large smartphones, it is often too wide for older devices (which are 320px wide). For a truly mobile-safe strategy, use 300×250 or 320×50 for phone users.
Best Practices for High-Converting Designs
- Keep the Message Short: You don’t have space for a novel. Stick to 8–12 words.
Example: “Launch High-Converting Ads in Minutes” - Use Strong Visual Hierarchy:
- Main Image
- Headline
- CTA Button
- Make the CTA Pop: Use a high-contrast button color (like orange or blue) that stands out against the background. Avoid “ghost buttons” (transparent buttons with thin borders) as they tend to get lower click rates.
- File Size Limits: Keep static images under 150 KB to ensure your ad loads instantly. A slow ad is an invisible ad.
Conclusion
The 336×280 Large Rectangle is a powerhouse for advertisers who want that extra bit of space to tell their story. By placing it inside content or at the end of articles, you can drive higher click-through rates and better brand visibility.