Answer: The most popular standard banner sizes offered by local publishers are:
(Measured in pixels (px)):
Button – 120x60px
Banner – 468x60px
Double Banner – 468x120px
Medium Rectangle – 300×250 px
Skyscraper – 120×600 or 160x600px
Half-page skyscraper – 300x600px
Leaderboard – 728×90 px
Sizes offered vary by publisher. In addition, each publisher has their own set of guidelines on the maximum kilobyte size (KB) of the creative as adverts that are too “heavy” can slow down the speed of the publisher’s website.