The iPad only went on sale outside the US on 28 May, but according to AdMob, it already has a big proportion of overseas users.
The mobile advertising firm says that according to its network stats, 38% of iPads accessing its network of ads in May were outside the US.
The biggest markets were Japan (5%), the UK (4%), China (4%) and Canada (3%), with three of those four getting a sharp boost in the number of iPad users over the weekend, once the device went on sale there.
China is the exception, yet according to AdMob's Mike Fyall, "we have seen consistently strong iPad usage in China since the device first launched".
AdMob tracked around 850,000 unique iPads during May.
The company has just launched its iPad SDK, allowing iPad developers to incorporate its ad units in their applications.