The International Advertising Bureau (IAB) is the only association dedicated to online, Interactive broadcasting, email, wireless and Interactive television media companies.

The quality of the IAB leadership, membership and industry initiatives, such as standards, research, advocacy and education, benefit the membership as well as the industry as a whole.

Interactive Marketing Units
The IAB guidelines for banners are listed below. These units are designed to enable web marketers to utilize greater interactivity as well as expand the creativity in their online messaging while adhering to an equal standard. (IMU = interactive marketing unit)

Rectangles and Pop-Ups
300 x 250 IMU - (Medium Rectangle) View IMU
250 x 250 IMU - (Square Pop-Up) View IMU
240 x 400 IMU - (Vertical Rectangle) View IMU
336 x 280 IMU - (Large Rectangle) View IMU
180 x 150 IMU - (Rectangle) View IMU

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)

Skyscrapers
160 x 600 IMU - (Wide Skyscraper)
120 x 600 IMU - (Skyscraper)