Duolingo isn't really intended to get you to B1. And even if it were, it would take more than six months to get there.
A commonly cited statistic is that it takes 360 hours in a classroom to reach B1. Duolingo claims to proceed faster than classroom hours, but there's enough fuzz in that number to suppose that it's closer to 1:1. You just can't realistically do 360 hours of Duolingo in six months.
Duolingo could at best help you reach an A3, and even then you'd have to supplement it with reading and (ideally) conversation. Duolingo plus outside reading and listening could get you to a B1 level in a year if you really put your mind to it.
They even make a podcast available, to help the listening part. I happen to listen to the French one myself, and highly recommend it. The stories are interesting and well produced, and bring stories (and accents) from all around the Francophonie.
Doing it with a personal teacher will always be better than an app, but Duolingo gives a huge jump start on that. For free.
They started adding B1 level content a couple years ago, although I agree with the overall point that it's probably not going to get you there on its own.
I just completed all of that content up to French level 1. It's helpful in introducing a lot of important-but-uncommon verb cases (conditional, subjunctive), but at least at level 1 I still wouldn't really be able to follow them in context.
It sure as hell doesn't help that in French they all sound the same. They're clear enough in written form, but French in particular requires close attention to context. Even other Romance languages draw the same distinctions more clearly.
One of the problems with the Spanish course is that all the later content (past checkpoint 5 or so) just stops explaining things at all, so it's up to the user to figure out things like how the negative imperative uses the subjunctive case. It's okay if you've taken a more structured language course in the past but I can imagine people starting from scratch just getting completely lost at that point.
A commonly cited statistic is that it takes 360 hours in a classroom to reach B1. Duolingo claims to proceed faster than classroom hours, but there's enough fuzz in that number to suppose that it's closer to 1:1. You just can't realistically do 360 hours of Duolingo in six months.
Duolingo could at best help you reach an A3, and even then you'd have to supplement it with reading and (ideally) conversation. Duolingo plus outside reading and listening could get you to a B1 level in a year if you really put your mind to it.
They even make a podcast available, to help the listening part. I happen to listen to the French one myself, and highly recommend it. The stories are interesting and well produced, and bring stories (and accents) from all around the Francophonie.
Doing it with a personal teacher will always be better than an app, but Duolingo gives a huge jump start on that. For free.