Certification
- Argentina:13
- Australia:PG (some episodes)
- Australia:M (some episodes)
- Brazil:10
- Brazil:12 (some episodes)
- Brazil:Livre (some episodes)
- Chile:TE
- Denmark:15 (DVD rating)
- Finland:K-13 (Season 1 DVD)
- Germany:16 (season 1)
- Germany:12 (season 2)
- Germany:12 (season 3)
- Germany:12 (season 4)
- Germany:12 (season 5)
- Germany:16 (season 6)
- United Kingdom:15
- United Kingdom:12 (most episodes)
- United Kingdom:PG (some episodes)
- United States:TV-G
- United States:Not Rated (DVD rating)