Best Mobile Ad Sizes in 2019: Find Out Which Banner Units (Standard, Small & Google Optimized) We Recommend

Best Mobile Ad Sizes in 2019: Find Out Which Banner Units (Standard, Small & Google Optimized) We Recommend

Best Mobile Ad Sizes in 2019: Find Out Which Banner Units (Standard, Small & Google Optimized) We Recommend

Do Mobile Ad Sizes really matter?

With an estimated 5 billion mobile users on the planet, engagement with mobile devices is higher than ever and continuously growing.

People of all ages, generations, and genders are using their devices wherever they go, some for even for hours per day. These users get bombarded by messages, news events, and social media on a daily basis – all very distracting.

This increases the need for mobile ads to be attention-grabbing, placed in optimal digital spots for maximum viewability while utilizing the best banner sizes for maximum revenue generation for publishers and successful campaign management for advertisers.

Let’s take a look at some of the best mobile ad sizes for publishers in 2019 and optimization tips you can start implementing today!

Running into costly errors with mobile ad ops? It’s overwhelming to learn the various techniques to start winning with mobile ads. That’s where we can help. Partner with MonetizeMore today to take on the mobile web and start increasing your mobile ad revenue today!


The 300×250 ad unit Google update

In 2017 Google changed their mobile ad types policies and removed restrictions placed 300×250 units above the fold. After rigorous testing, Google determined that these 300×250 ads can be implemented above the fold in a way that does not annoy or distract users.

This change is excellent news for publishers as it gives them a chance to earn better CPMs (cost per thousand impressions). Since the 300×250 unit is a high performing ad unit, being able to place it above the fold leads to good viewability and a high potential for user engagement.

Read more about the update and best practices here: Mobile ad policy gets a revamped: 300×250 ATF

The image below demonstrates viewability compared to ad placement of the 300×250 unit.

Buyers tend to favor this placement as it is the first thing users see on a mobile site’s landing page. Compared to the small banner sizes (e.g., 320×50), bigger mobile display ad sizes (e.g., 300×250) usually generate better revenues.

However, being too aggressive with your ad placements can increase the chances of accidental clicks and lead to negative user experiences. As a publisher reliant on one of Google’s networks for monetization, whether it’s Ad Exchange or AdSense, you don’t want to risk getting your account banned.

For this reason, it’s best to follow Google recommendations and only have 50% of the ad viewable above the fold. The image below provides excellent examples of successful 300×250 as well as 300×50 mobile ad specs and placements.

google standard mobile banner sizes - small and large 300x250 & 320x50

More mobile ad unit sizes to consider

Larger advertising formats (e.g., mobile interstitial ad sizes) have been proven to be better at capturing the user’s attention and paying the best CPM rates, but publishers should be careful with intrusive ad formats in 2019 on both mobile and desktop versions of their sites.

Effective February 15, 2018, Google will update it’s Chrome browser with a built-in ad blocking tool in agreement with the Coalition For Better Ads standards and will stop showing all ads on sites that have been in “Failing” status for more than 30 days.

Be sure to read our Google Chrome Adblock Policy Update 2018 post to find out how to check if your mobile ads comply and to fix any potential issues.

There’s a non-stop search for creative ways to deliver ads on mobile, thus the birth of these large ad formats which up to now, continues to grow.

In a recent study from Adpiler, 300×250 mobile ad size was found to be the most popular ad size. 34% of all ad impressions is this medium rectangle.

A study conducted by Medialets on Q1-Q2 of 2014 reported that among static formats, full-screen interstitials tend to generate more clicks than their smaller counterparts – both in smartphone and tablet ad sizes (see the image below as reference).


The 300×250 Medium Rectangle tends to perform the highest on both handsets and tablets regarding CTR. Remember, this could change depending on the ad placement and ad style.


Typical sizes of banner ads on smartphones are the 320×50 units whereas larger ad formats such as 300×250 and full-screen interstitials (320×480) have been proven to yield higher engagement rates.

The most standard mobile banner ad sizes for tablets is 728×90 whereas full-screen interstitials such as 768×1024 and 1024×768 ad units are known to yield strong engagement rates.

Bottom line

Mobile display Ad size is a critical driver towards advertising effectiveness and performance. The smaller the size, the harder it is to capture user attention and drive engagement.

Optimization Tips

1) The mobile banner 320×50 is best implemented as a docked/anchor unit. That’s when it performs better regarding CTR. Since it’s a small ad unit, when served as a regular banner, 300×250 and 320×100 units usually outperform it.

2) “Scroller,” an emerging ad unit that fills the screen without covering the entire content is one approach to ad-blocking concerns. According to the IAB’s report, this type of ad format is non-invasive (the users can scroll past them) and has outperformed expandable banners regarding creativity and enjoyment.

3) Medium Rectangle (300×250) remains to be the best performing banner size. Take advantage of the opportunity to implement it above the fold.

4) In-banner Video (IBV) providers favor 300×250 most of the time. They usually pay the best CPMs which you can compete against Header Bidding to push performance up. When running IBV, try to limit it to two units at most to avoid slowing down the page.

Be careful not to overwhelm your users with too many interstitials per user session. It may turn them off, and they may avoid your site altogether in the future. Should you decide to try interstitials or other intrusive ads, remember the guidelines on the previously mentioned Ad Experience Report.

5) The “Large Rectangle” (336×280) is also a top performing ad size as suggested by Google. Make your ad unit flexi by adding it along with your standard mobile ad sizes (e.g., 300×250 / 336×280). It has been proven to perform well when embedded within text content or at the end of articles.

6) Aside from the ad size, one advantageous feature of mobile devices is the location service plus. This makes advertising more relevant to users and potentially generate higher clicks. If you are using an ad server, like Google DFP, geographical targeting will play a significant role. Most ad networks can specify the countries where they have campaigns available.

7) Check your ads for aesthetics. Keep only those ad networks that serve high definition quality creatives and ditch the pixelated ones regardless of the CPM’s they promise. You can’t afford to compromise on user experience. Ads that are non-pixelated tend to yield positive engagement rates and leave a positive impression on users.

8) You can have multiple ad sizes compete in the same ad spot to tighten competition. For instance, you can have a 300×250 spot serve 320×100 and 320×50. When this happens, the smaller advertisements will always align vertically at the top.

9) Get the best deals on Ad Networks. Several ad networks are offering flat-rate CPMs for interstitials and other mobile ad sizes. At MonetizeMore, we have demand partners who can provide as much as $10 CPM for mobile slider ads, interstitials, anchor unit, etc.

Read more mobile optimization tips from Google here.

What’s next?

Don’t know where to start with your mobile inventory? Made one too many costly errors already? Partner with MonetizeMore and we will help you navigate the complex landscape of mobile ad optimization to make sure your ad revenue grows in the right direction. Sign up today!

Related Reads:

Get my ad optimization tips and tactics delivered to your mailbox.

Kean Graham

CEO and Founder at MonetizeMore

Kean is the resident expert in Ad Optimization covering areas like Adsense Optimization, DFP Management, and third-party ad network partnerships. Kean believes in the supremacy of direct publisher deals and holistic optimization as keys to effective and consistent ad revenue increases.


  1. Hello, thanks very much for your great info about google adsense for mobile, i have been looking for this info and i thank God i have come across it on your site,i have a website known as: but i foundout that when someone vists it using a mobile device, the adsense ads donnot display.

    So i want to try the 320/50 and see if it will work.

    L.James @

  2. Sir which is the best ads format I am getting 0.02 cpc

  3. That is a very well written and in-depth information / experiment of each ad unit, surely be helpful, Thank you!

  4. nice website good post sir

  5. Thank you- I thoroughly enjoyed the data provided and simple feedback. We are implementing a new strategy on our website and I was just about to throw out standard ads on mobile when I googled research on ad performance and found your article. You saved the day- thanks again!

  6. Thanks for your article. this is very usefull article for people. thanks admin.

  7. Very informative!


Submit a Comment

Your email address will not be published. Required fields are marked *