Unterhaltungssoftware Selbstkontrolle is Germany's most prominent video game rating system based in Berlin. It was founded in 1994. It considers itself to have the strictest age classification rules in the world. It gives games one of five different ratings depending on content. Retailers can't sell games with a high rating to people whose age is lower than that rating. Games without a USK rating are treated as if they are rated USK 18 regardless of content.
Its website can be found here (in English).
The age ratings USK uses:
USK 0
The lowest rating. As the name implies, games with it have no age restrictions and can be sold to anyone.
Games with this rating are directly aimed at children, family-friendly games and other games that don't require child protection laws of any kind.
Other rating systems' counterparts to this rating:
- Entertainment Software Rating Board's Early Childhood Rating and Everyone Rating
- Pan European Game Information's PEGI 3 rating
USK 6
The second lowest rating. As the name implies, games with it can only be sold to people six or more years old.
Games with this rating are still family-friendly, though they're usually meant to be more exciting or competitive.
Other rating systems' counterparts to this rating:
- Entertainment Software Rating Board's Everyone Rating and Everyone 10+ Rating
- Pan European Game Information's PEGI 7 rating
USK 12
The middle rating. As the name implies, games with it can only be sold to people twelve or more years old.
Games with this rating often have a competitive edge. They're also often set in a historical, futuristic or fantastic setting, allowing players to distance themselves from the events.
Other rating systems' counterparts to this rating:
- Entertainment Software Rating Board's Everyone 10+ Rating and Teen Rating
- Pan European Game Information's PEGI 12 rating
USK 16
The second highest rating. As the name implies, games with it can only be sold to people sixteen or more years old.
Games with this rating often feature acts of violence, armed combat, framework story and military missions.
Other rating systems' counterparts to this rating:
- Entertainment Software Rating Board's Teen Rating and Mature Rating
- Pan European Game Information's PEGI 16 rating
USK 18
The highest rating. As the name implies, games with it can only be sold to people eighteen or more years old.
Games with this rating often feature violent content as well a dark and opressing atmosphere. Stories may have basis in war or battle between rival gangs.
Other rating systems' counterparts to this rating:
- Entertainment Software Rating Board's Mature Rating and Adults-Only Rating
- Pan European Game Information's PEGI 18 rating