A video game content rating system is a system used for the classification of video games into suitability-related groups. Most of these systems are associated with and/or sponsored by a government, and are sometimes part of the local motion picture rating system

Motion picture rating system

A motion picture rating system is designated to classify films with regard to suitability for audiences in terms of issues such as sex, violence, substance abuse, profanity, impudence or other types of mature content...

. The utility of such ratings has been called into question by studies that publish findings such as 90% of teenagers claim that their parents "never" check the ratings before allowing them to rent or buy video games, and as such calls have been made to "fix" the existing rating systems. Video game content rating systems can be used as the basis for laws that cover the sales of video games to minors, such as in Australia. Rating checking and approval is part of the game localization when they are being prepared for their distribution in other countries or locales.
These rating systems have also been used to voluntarily restrict sales of certain video games by stores, such as the German retailer Kaufhof

Metro AG

Metro AG is a diversified retail and wholesale/cash and carry group based in Düsseldorf, Germany. It has the largest market share in its home market, and is one of the most globalised retail and wholesale corporations. It is the fourth-largest retailer in the world measured by revenues . In English...

's removal of all video games rated 18+ by the USK following the Winnenden school shooting

Winnenden school shooting

The Winnenden school shooting occurred on the morning of 11 March 2009 at a secondary school in Winnenden, Baden-Württemberg, in southwestern Germany, followed by a shootout at a car dealership in nearby Wendlingen. The shooting spree resulted in 16 deaths, including the suicide of the perpetrator,...

.

(Protect)
| colspan="6" style="background:orange;" |輔
(Counsel)
| style="background:black; color:white" |限
(Restrict)
|colspan="1" style="background:black; color:white;" |unknown
| style="width:150px; line-height:75%;" | Protect- and Counsel-rated games should be played with parent or guardian's supervision.
|-
!   ESRA
| colspan="3" style="color:grey" |
| colspan="4" style="background:lime" |+3
| colspan="5" style="background:Yellow;" | +7
| colspan="3" style="background:orange;" | +12
| colspan="2" style="background:red; color:white;" | +15
| colspan="2" style="background:black; color:white;" | +18 & +25
| style="width:150px; line-height:75%; " | Some games are forbidden. Games with Intense Violence, strong sexual content or Nudity are prohibited.
|-
! TIGRS
| colspan="9" style="background:lime" |Family Friendly
| colspan="7" style="background:orange" | Teen Content
| colspan="3" style="background:black; color:white;" | Adult Content
| style="width:150px; line-height:75%; " | Created for the use of games produced by independent developers
|-
! Apple Inc.
| colspan="3" style="color:grey" |
| colspan="5" style="background:lime" |4+
| colspan="3" style="background:yellow" |9+
| colspan="5" style="background:orange" |12+
| colspan="3" style="background:black; color:white" |17+
| style="width:150px; line-height:75%; " | Created for games distributed through Apple's App Store worldwide
|-
! Newgrounds

Newgrounds

Newgrounds is an American entertainment and social media website. Founded on July 6, 1995 by Tom Fulp, the site primarily hosts Adobe Flash animations and games, but also features a music-oriented page, along with an art portal...

| colspan="12" style="background:lime" | All ages/ Everyone
| colspan="4" style="background:orange" | Teen
| colspan="1" style="background:red; color:white;" | Mature
| colspan="2" style="background:black; color:white;" | Adult
| style="width:150px; line-height:75%; " | A content rating system developed in flash games by the website Newgrounds. The developer of the game decides the rating themselves.
|}

•  Spring Green + Lime  – All ages may play.
•  Yellow  – Parental guidance is suggested.
•  Orange  – Not recommended for a younger audience but not restricted.
•  Red + Pink  – Restricted to adults only unless accompanied by an adult.
•  Black  – Restricted to adults only. Unknown is also in black

Explanations of specific ratings are available in corresponding articles.