The Ultimate Guide to Web Banner Sizes

Whether you are launching a digital marketing campaign, designing a portfolio website, or learning the ropes of graphic design, understanding web banner sizes is essential. Using the correct dimensions ensures your graphics look sharp, load quickly, and fit seamlessly into standard advertising networks like the Google Display Network.

Because digital real estate varies wildly across desktops, tablets, and smartphones, knowing which dimensions matter most will save you time and maximize your campaign’s reach.

The Core Five Banner Sizes

While dozens of display ad dimensions exist, a handful of standard sizes dominate the web. Focusing on these core formats covers the vast majority of available digital inventory:

• 300×250 pixels (Medium Rectangle): Widely considered the single most important display ad size. It fits smoothly inside sidebars, between paragraph content, or at the end of articles on both desktop and mobile devices.
• 728×90 pixels (Leaderboard): The classic horizontal banner traditionally placed at the very top (header) or bottom (footer) of desktop web pages.
• 160×600 pixels (Wide Skyscraper): A tall, vertical banner built for desktop sidebars. Because of its placement, it often stays visible (“sticky”) as the user scrolls down a page.
• 300×600 pixels (Half-Page / Large Skyscraper): A high-impact vertical unit offering double the height of a medium rectangle. It is popular for brand storytelling and high-visibility placements.
• 320×50 pixels (Mobile Banner): The dominant format for mobile web browsing. It is typically pinned to the top or bottom of a mobile screen for constant visibility.

Standard Web Banner Sizes Reference Table

| Size (Pixels) | Common Name | Typical Device | Best Placement |
| :— | :— | :— | :— |
| 300×250 | Medium Rectangle | Desktop & Mobile | In-content, sidebars |
| 728×90 | Leaderboard | Desktop | Header or footer |
| 160×600 | Wide Skyscraper | Desktop | Right/left rail sidebar |
| 300×600 | Half-Page | Desktop | Sidebar or embedded in articles |
| 320×50 | Mobile Banner | Mobile | Top/bottom of mobile pages |
| 336×280 | Large Rectangle | Desktop & Mobile | Inside content-rich layouts |
| 970×250 | Billboard | Desktop | Premium header takeovers |

Designing for Different Devices

One of the biggest mistakes designers make is trying to reuse a desktop banner layout directly on mobile screens.

• Desktop Layouts: Offer more room to breathe. Formats like the Leaderboard (728×90) and Skyscraper (160×600) allow for detailed imagery, multi-line headlines, and generous whitespace.
• Mobile Layouts: Require extreme simplicity. Because mobile screens are compact, banners like the 320×50 need a bold logo, a short headline, and an unmistakable Call to Action (CTA) that users can process in a single glance.

Best Practices for Web Banners

1. Keep File Sizes Light: Most major ad networks require display banners to stay under 150 KB to ensure the host web page loads smoothly.
2. Prioritize the CTA: Every banner should have a clear goal—whether it is a “Learn More,” “Shop Now,” or “Sign Up” button that stands out from the background.
3. Use the Right Formats: Export static banners as crisp JPEGs or PNGs, or use lightweight GIFs if animation is required.

By starting with the core five dimensions and tailoring your layout to the device, you can create clean, high-performing web banners for any digital project.