There are currently 4.68 billion mobile users around the globe. These are users from different geographical locations, of different ages, and status (financial and socioeconomic). This creates a huge pool of users and an opportunity for publishers to bring them to their website and show relevant ads.

Moreover, 70% of world internet usage is on mobile devices. And each individual spends approximately 3 hour 35 minutes on his/her mobile device per day. Therefore, we can infer that mobile advertising is both the present and the future of online advertising.

Now, let’s say you want to give mobile advertising a try. But where to start? What type of ads  work on mobile? And what is the best mobile ad size? These are the common questions for every publisher.

Let’s answer these questions, once and for all. Here are the best mobile ad sizes categorized by ad formats to help publisher pick the right one.

Mobile Banner Ads

One of the most popular ad formats, mobile banner ads are preferred by most publishers and advertisers. For mobile advertising, banner ads are often considered as a safe-to-start-with option. Also, banner ads appear in form of box, bar, or column with image and text on the user’s screen.

Banner ads are good for small-to-medium publishers who are just starting out with mobile advertising. However, there are premium publishers (like Huffington Post) who use banner ads on their sites. With the right placement and better user engagement, any publisher can make a good earning with mobile banner ads.

Popular Mobile Banner Ad Sizes:

• Mobile leaderboard: 320×50.
• Medium rectangle: 300×250
• Large mobile banner: 320×100

Tips to get started with mobile banner ads:

• Do not block the content with ads and place banner ads precisely among content.
• Experiment with different banner ad sizes rather than settling for one.
• Do not ask for clicks or place ads in such a way that they get accidental clicks.
• Do not put too many ads in proximity which affect the user experience.

Mobile Video Ads

According to eMarketer, mobile video advertising will exceed all other advertising methods by 2020. The reason for such a boost is user demand. Users like to see videos (in the form of ads too) and advertisers want to go with what users want. A US adult spends averagely 5.5 hours on mobile device watching videos.

However, video mobile advertising can be costly for the demand side. And for publishers, it can increase the page load time. Although, the user demand to see more videos is pushing the market to invest in video ads even with the existing challenges. Also, for video content publishers, video ads are a boon and work perfectly for their inventory.

Here we can say, mobile video advertising is a bittersweet situation for publishers.

The preferable mobile ad size for videos are 320*480 and 480*320. However, you can go with the size that suits your inventory, user preference and advertiser’s demand.

Tips to get started with mobile video ads:

• If you are a video content publisher, go for in-stream video ads. For other publishers, choose outstream video ads.
• Since video ads are costly, advertisers look for an inventory which is worth spending money on. Hence, publishers looking to benefit from video advertising should optimize their inventory as per advertisers’ need (which is high pageviews and quality content and audience).
• Make sure video ads are short (about 15 to 30 seconds) and to-the-point to grab users’ attention as soon as they appear.

Rich Media Ads

Rich media ads are high-quality graphic ads which are responsive to user interaction (such as leaderboard ad that opens up on sliding). It can be a video, audio, and image encouraging users to interact. Because these are rich, interactive ads, they are also heavy in file size.

Rich media ads are popular among app publishers. Although more mobile web publishers are beginning to showing fascination for these ads. For mobile device, 600*500 and 320*480 are the optimal sizes for rich media ads.

Tips to get started with Rich Media Ads:

• They should be interactive, not intrusive.
• These ads may cover the entire screen of the user. If this happens, there should be an exit button to remove/minimize the ad.
• Do not force a user to interact with the ads.
• Try to keep the animations in the ad subtle yet effective.

Interstitial Ads

Interstitial ads are widely used on the mobile app interface. These are interactive ads that cover the entire screen on the user device and show ads in banner or video format. Interstitial ads are often placed between the natural transitions of a mobile app such as different activities or game levels. The preferred size of the interstitial ads are 320×480 and 480×320.

Publishers like Airbnb and Pinterest have seen significant increase (300% and 100%, respectively) in their installation rate by using interstitial ads as a marketing method. Meaning, these ads can be good for awareness, hence, to get better CTRs.

However, it’s also true that 22% users look for close button when interstitial ads appear on their screens. Meaning, if not used properly, interstitial ads can be bad for publisher’s revenue.

Tips to get started with interstitial ads:

• They need to be placed precisely between the natural breaks or transitions of an app/site and should not disrupt ongoing user activities.
• To close these ads, users need to interact (click). Make sure the close buttons are properly placed on the ads not encouraging any accidental clicks.
• Be sure that interstitial ads are right for you. Generally, interstitial ads are recommended for mobile application publishers.
• Adhere to the interstitial ads best practices to avoid penalties.

Mobile Native Ads

Native ads are non-intrusive form of advertising, commonly used for both, desktop and mobile advertising. Native ads have the look and feel of organic content on the screen. These ads can be seen as ‘promoted’ and ‘suggested’ content placed on sites. The size of native ads depends on the size of the content on the website. They generally mimic the content type, style, format, and size.

Native ads blend with content and hence get users’ attention. Also, a well planned native ad can be informative and encourages click, examples of which are all around us—Twitter claimed it got a 198% increase in ROI using promoted tweets, a native ad format

Tips to get started with mobile native ads:

• Native ads don’t interrupt the user experience. However, publishers must place native ads under ‘promoted’ or ‘sponsored’ block.
• Native ads are suitable for publishers having a highly engaged audience.
• Try to use native ads and display ads together to make the most out of both.

Final Word

There is no perfect ad size for all publishers. You need to look for what best suits your website. For instance, if you have a mobile app, interstitial ads will work well. Or in case you have content-loving users, native ads would be a good choice.

Similarly, you might also want to try two or three ad types and sizes for your inventory. Next, run tests with the above mentioned mobile ad sizes and formats. Lastly, never forget to consider your users’ experience while putting different ad sizes.

So what should you do next? Get in touch with a good mobile ad network, ace your research on mobile ad size and format, and start with mobile advertising.