Epic Games says its free Unreal Development Kit for PC has already attracted some 50,000 users worldwide since it launched just a week ago.

The newly-announced UDK toolset offers no-cost access to developers and students of all levels interested in using Unreal Engine 3's toolset for non-commercial development. Creators still need an official licensing agreement to develop a commercial project.

Epic will continue to support UDK's users -- which span 130 countries and 4,500 cities worldwide -- with documentation as well as free updates that keep its features in step with those of Unreal Engine 3.

"We are very excited to see the uptake of UDK cross over the 50,000 mark in only one week, and we're looking forward to seeing amazing games and applications come out of it," says Epic VP Mark Rein.

"We're also thrilled to finally be able to offer UDK free for schools and students so they can work with the same awesome Unreal Engine 3 tools used by many of the top game developers and publishers around the world."