Google Campaign Manager technical specs
Animated banners (animated GIFs) can loop only three times, and the total animation can’t exceed 15 seconds. Repetitive or rapid flashing, blinking in excess, or visually stressful animations aren’t allowed.
Max file size is 500KB.
Only one asset is required to display in both portrait and landscape orientation.
Assets may only be produced as JPEG, GIF, PNG, or HTML5.
Specifications are optimized for all supported devices.
Only one asset is needed for all supported iPhone and iPod touch devices, and one for all supported Mac computers and iPad devices.