Banner Ad Size Guide

The size of your banner Ad can have a surprisingly big impact on how well or not so well your Ads perform. So, choosing the right sizes can really boost your overall campaign reach and generate the outcome you desire.

There are a variety of sizes to choose from and some are used more frequently than others depending on what it is you are advertising. Choosing the wrong sizes can cost you money in wasted design efforts and the cost of placement on Ad platforms. A few examples of the best sizes are The Medium Banner, Leaderboard, Wide Skyscraper and Billboard. These banner Ads are carefully positioned around the webpage in different areas. For instance, the Billboard can be seen directly at the top and in the centre of a webpage, instantly catching the eye of the reader.

Web Banner Sizes

There are standardised guidelines on banner sizes which can be used across all advertising networks such as the Google Display Network.

Different websites will follow the guidelines and you will be required to ensure your banner fits, so you can upload it. Getting your banner into the right size is a simple process and can be done easily online or from your computer.

Ad sizes are slightly different for mobile usage. There also seems like there are so many to choose from when picking your ads however, the vast majority of impressions are made up of only 4 of the most common sizes which narrows down the selection for you.


Most Popular Ad Sizes

Despite there being a wide range of banner sizes to choose from, there are only 4 variations that are most commonly used in the digital advertising world.

It is thought that approximately 89% of all advertising impressions are made up of the following:

  • The Leaderboard 728 x 250 – taking a quarter of all impressions
  • The Medium Rectangle 300 x 250 – nearly half of all impressions
  • The Wide Skyscraper 160 x 600
  • The Mobile Leaderboard 320 x 50

When it comes to planning and arranging your display campaigns, it is advised to focus on these four sizes to get the maximum outcome from your ads.

Best Banner Sizes for Mobile

In the current digital climate, more or less everywhere allows for a mobile friendly online experience. If you haven’t yet incorporated a mobile friendly experience for your users, now is the time to get this resolved as the majority of people use their phones as their main source for browsing.The mobile experience passed desktop delivering approximately 63% of all internet traffic back in 2017.

Similarly, to standard banners there are several mobile ad sizes available but there is a stand out format that beats the rest. This format is the 320 x 50 Mobile Leaderboard. If you want to maximise reach through your banner ads then the Mobile Leaderboard is the way to go.

The Mobile Leaderboard is one of the best banner sizes for mobile and it can be found at the bottom of apps and embedded into content at the bottom of a phone screen web page.

With heavy reliance on apps for most aspects of our lives (handling our money, travel, entertainment, socialising and beyond) which means apps are becoming, if not already, the most common way in which people consume their content. It’s likely people travelling to and from work every day will read the news on their commute or they might open a music app to hear their favourite playlist. If you are looking to reach far and wide to potential customers whilst they are browsing through apps, then this is the best thing to use.

The Medium Rectangle Banner

The Medium Rectangle Banner is another one of the best banner sizes working well on both mobile and desktop. Its size is 300 x 250 and is the most popular Ad banner size of all global inventory with 40% reach in total. It’s the most compact out of all the options and takes up a good amount of space on the page.

You want the Medium Rectangle Banner in your advertising kit because it works brilliantly on desktop and phone with a high reach percentage, it’s a good option for when you are just starting out with display ads.

When it comes to the desktop setting, you will find this type of Ad embedded in content in either the top right or left corner of a webpage. In addition to its already popular usage, it also works really well as a text version or an image Ad.

Its size enables the Ad to be seen very clearly in a really good eye-catching spot without being too intrusive to the audience. You can often find The Medium Banner Ad in content such as blogs and other articles. When using a mobile to view these Ads, this format will act as a break within the page, chopping up the content into more bite sized pieces. If the ad is designed appropriately, this will be taken as a welcomed break to the viewer instead of an intruder on their reading.

The guidelines for this style of banner have been issued from Google and are quite specific. It’s important to remember to stick to the size guidelines because Google has the right to remove your ad from the Google Display Network if your sizing is incorrect. The Google Display Network covers approximately 2 million websites that reach up to around 90% of all internet users so it’s worth keeping to them.


Full guidelines from Google can be found online but some of the examples are as follows:

  • The ads cannot cover the content of the app
  • Ads must be clearly distinguishable from the app content
  • Avoid accidental clicks on the banner by not placing it in too close proximity to other interactive parts of an app, like a navigational menu or chat box
  • Close buttons should not overlap or be adjacent to the Ad, since this causes a lot of accidental clicks

All Ads should be easily distinguishable from the content of the app, it should not clash with it in any way. If it is clear that your Ad is indeed an Ad, and users understand that is what they are looking at, then you’re good to go.

The Leaderboard Banner

The 728 x 90 Leaderboard Banner is up there on the best banner sizes list. This is known as a Horizontal Banner and is the second most popular Ad size within the digital marketing world, its impressions reach around 25%.

When browsing on desktop, this style of banner is displayed noticeably at the top of a webpage taking up over half of the banner space. Sometimes these banners can be embedded at the bottom of a webpage too.

Ads that are displayed at the top of a webpage usually have a higher performance rate than those at the bottom of a webpage. This is simple because it’s rare that users will scroll all the way to the bottom of a page. If they do, they may have had enough of reading content and are likely to have lost interest. It’s best to locate them at the top to grab the attention of the reader instantly. Google also advises using this banner ad size on forum sites.

The Wide Skyscraper

The Wide Skyscraper falls under the bracket of the Skyscraper format. These particular styles of Ads are unfortunately not mobile friendly and the amount of reach they have is not massive however, they are still used frequently throughout desktop browsing.

The size comes in at 160 x 600 and has an approximate reach of around 12%. There is another variation of this Ad which is slightly smaller coming in at 120 x 600 and is aimed at websites that don’t have the room to accommodate the Wide Skyscraper. If you do have a choice, it is always advised to go with the Wide Skyscraper and this is simply because more websites use the Wide Skyscraper banner size than its slimmer counterpart.

The Wide Skyscraper can be found either to the left or right hand side of a webpage and it stretches down the side rather than across it, hence its name. This banner format also works really well in either text or image.

Out of all the best banner sizes, sadly the Skyscrapers come in last and are in slow decline.

Mobile has taken over desktop use and because this format isn’t compatible with mobile, it is becoming less and less relevant. Of course it is still advisable to implement a Skyscraper Ad on desktop for those who do still browse that way but if you are choosing and have limited access to resources, your focus would be best spent on those that are both desktop and mobile friendly.


There are  4 main varieties of ads that are the best formats to ensure you hit your target reach across both desktop and mobile:

  • The Leaderboard 728 x 250 – 25%
  • The Medium Rectangle 300 x 250 – 40%
  • The Wide Skyscraper 160 x 600 – 12%
  • The Mobile Leaderboard 320 x 50 – 12%

Flexible solutions to suit your business