User blog:Herewithoutachange/Rating systems we could use, and their MPAA equivalents

Exhilaration Animation Rating System (EARS)

 * All ages (ALL) / G
 * Child (7+) / PG
 * Teen (12+) / PG-13
 * Mature (16+) / R
 * Adult (18+) / NC-17
 * Whoa (:/) / No equivalent
 * No (this is not okay) / No equivalent

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k system

 * k for 0+ (k0) / G
 * k for 6+ (k6) / PG
 * k for 12+ (k12) / PG-13
 * k for 16+ (k16) / R
 * k for 18+ (k18) / NC-17

Number-Based Rating System (NBRS)

 * 3 / G
 * 7 / PG
 * 12 / PG-13
 * 16 / R
 * 18 / NC-17

Make your own rating system
Leave your own rating system idea in the comments.