What is a 125×125?
The 125×125 ad unit is a now-defunct IAB standard ad unit with the dimensions of 125 pixels wide by 125 pixels tall. The 125×125 was retired in 2011 by the IAB.
This ad size was referred to as a Button, along with the 120×60. It was retired due to a lack of prevalence in the marketplace, however, it was mainly used on listings sites in the past and it continues to be used by them now.
A 125×125 ad unit is most commonly used for freemium listings, and in our opinion looks slightly better than the other Button ad (the 120×60).
125x125s generally do not cost much, as they do not perform very well. However, as they are less prevalent than even the 120×60 ad unit, they are not really very useful at all any more to anyone except freemium listing sites.
What it looks like
The Tile ad unit dimensions are 125 x 125 pixels. Below is a live example of this ad unit.
Note: The live ad may not always load for technical reasons, and instead a backup image will show.
125×125 Advice for Site Owners
While 125x125s look slightly better than 120x60s, these ads are not recommended to anyone. The only exception to this recommendation is to listings sites which are currently using them, as changing to 120x60s might confuse and irritate your advertising base.
125x125s are only really useful for freemium listings, as they are something you can give away without much cost to you as added value. We would recommend using 120x60s if you are going to go down this path as both units are about equal in their (lack of) value, but 120x60s take less space.
Outside of listing sites, this ad unit generally looks out of place or that it is part of an affiliate link. Either way is not great for your site, so they should be ignored.
125x125s Advice for Ad Buyers
Button ad units are not common outside of listing sites, so any other type of site using them probably doesn’t know what it’s doing and should be avoided.
If you have a choice between this ad unit and a 120×60, we would recommend this one as it is slightly larger. However, as 120x60s are much more prevalent, if you are not buying specific ad space, we would recommend creating 120x60s above this ad unit.
We would not recommend either type of button to ad buyers in general.