I am a merchant and am setting up an affiliate program right now. I have read that 468×60 is the standard banner size, but I was wondering if you can give me some idea of other popular sizes and (better still) their popularity ranking.
Yes, 468×60 is one of sixteen standard banner sizes per the IAB Interactive Marketing Units Standards.
Below are the standard banner sizes:
Rectangles and Pop-Ups
300 x 250 IMU – (Medium Rectangle)
250 x 250 IMU – (Square Pop-Up)
240 x 400 IMU – (Vertical Rectangle)
336 x 280 IMU – (Large Rectangle)
180 x 150 IMU – (Rectangle)
Banners and Buttons
468 x 60 IMU – (Full Banner)
234 x 60 IMU – (Half Banner)
88 x 31 IMU – (Micro Bar)
120 x 90 IMU – (Button 1)
120 x 60 IMU – (Button 2)
120 x 240 IMU – (Vertical Banner)
125 x 125 IMU – (Square Button)
728 x 90 IMU – (Leaderboard)
160 x 600 IMU – (Wide Skyscraper)
120 x 600 IMU – (Skyscraper)
300 x 600 IMU – (Half Page Ad)
As far as popularity, that only tells half of the story. The more important measure is the effectiveness.
In my experience, the 468×60 is the most popular banner. However, the most effective size in the affiliate programs I have managed has been the 120×90.
I would suggest testing a variety of the sizes above (ask your affiliates which sizes they want), and narrow down to the handful of sizes that are most effective for your affiliate program.
All that said, don’t focus solely on banners – be sure to also provide plenty of text ads for your affiliates. I’ve found that they outperform all of the banner ads.