Ad Size Guide

Welcome to our Ad Size Guide, where we explain everything you need to know about the most prevalent ad sizes available within the world of online advertising. The IAB keeps a list of ad sizes here which it recommends to people, however as we at The Online Advertising Guide have a slightly different take to them, we thought it would be helpful to give our advice too.

In our Ad Size Guide we cover each ad size from the point of view of both people looking to sell advertising space on their site, and people thinking about buying online advertising and looking for advice. Every ad size contains both descriptions so that you can not only see what issues you have to consider and overcome from your point of view, but also what the person at the other end of the phone (or email) is thinking about too.

To start with we have a little bespoke overall advice for each group, so are you looking to sell ad space, or use online ads for marketing? Or are you trying to understand terms related to ad sizes?



If you think you already know it all, why not try our Display Ad Size Quizzes and prove it?


Best Desktop Ad Sizes

160x600160×600 Wide Skyscraper 300x250300×250 MPU / Med Rec 300x600300×600 HPU 728x90728×90 Leaderboard 970x250970×250 Billboard


Best Mobile Ad Sizes

300x50300×50 Mobile Banner 320x50320×50 Mobile Leaderboard 320x100320×100 Large Mobile Banner 320x480320×480 Mobile Interstitial


Less Common Display Ad Sizes

120x60120×60 Button 125x125125×125 Button 970x90970×90 Super Leaderboard


Site Takeovers

SponsorshipsSponsorships Homepage TakeoverHomepage Takeover ReskinReskin


Intrusive Ads

OverlayOverlay / Floater Pop UnderPop Up / Pop Under


Other Types of Ad

In-Text AdvertisingIn-Text Advertising Mobile AdvertisingMobile Advertising Pre-RollPre-Roll Advertising Skippable AdsSkippable Ads


Old Display Ad Sizes

120x600120×600 Skyscraper 336x280336×280 Large Rectangle 468x60468×60 Banner


Next: Ad Sizes for Ad Buyers