Despite the look of the movie, it's not for young kids.
If the movie were rated only for the violent scenes, it probably would have been a PG. With the exception of a yucky-looking wound caused by alien spiders, the violence was pretty tame. But the language and innuendo were too strong for what should have been a family film.
This is a heavily modernized version of the old Lost in Space TV series. It's funny and interesting, and the characters are memorable. I liked the movie. There are several extremely gross parts, however, that have to do with spiders, and a man being eaten by spiders. I recommend it for ages 12+, or maybe a little younger, depeding on the person's nausea tolerance. : )