Responses
Not really sure, but ig the shoujo is aimed primarily at a young female audience, while josei is aimed at more mature female audience (ofc it doesn't matter what your gender and age is you can read whatever you want)
Plus shoujo, generally deals with "less mature" themes like first love, highschool, ...ect. while josei tackles more mature themes like marriage, divorce, sexual relationship...ect. generally both of them are made by female authors.
Hope this helped, you can search more on Google or just read bunch of shoujo and josei and you can easily say the difference between them.
guys, anyone care to explain what's the difference of shoujo and josei?