There are going to be some down and dirty spoilers for Sausage Party in this article, so parental discretion is advised.
According to the Guardian, Sweden has given Sausage Party a rating of 11, which is basically the equivalent of PG here in the states.
In Sweden, Sausage Party can be seen at ages as young as seven.
As to why Sausage Party – a film that has a literal douche as the villain – was given a surprisingly low rating by American standards, it has to do with how the Swedish rating system works.