Any grade that gets the diploma is a good one! It’s a challenging course that requires a lot of commitment, so be proud of whatever you’re aiming for.
For context, however, below is the graph for the distribution of points awarded in the IBDP. The mean score in May 2020 was about 30 points. Over 30, and you’ll be above average!

Universities differ widely in their grade requirements, though – check the university admissions section for more information!