As you’d expect for a city of Frankfurt’s size, there are a number of institutions with university status. There are also some (business schools in particular) with no accreditation but I am leaving those out :-).
The main places are as follows:
Goethe University is a large state university with campuses in Westend and Riedberg. The uni covers a lot of subjects with 45,000 students enrolled at the moment. Compared to many universities in Germany it is pretty well-funded, partly thanks to its endowment, which is unusual over here. The university is ranked roughly as one of the top 20 institutions in the country depending on where you look.
For the non-German speakers there isn’t much to look at at Bachelor level. You need C1 German to enrol, or B1 German to get into a prep course to improve your German before studying. At Masters level, it is a bit better as there are about 10 Masters degrees taught totally in English and many more
Frankfurt University of Applied Sciences is the smaller more local/German relation of Goethe University. The uni, as its name suggests, is more technically focussed. It has only 4 Masters programmes taught fully in English and a number of individual modules for exchange students taught in English. Its website is completely set up to confuse non-German speakers :-). Therefore if you want to study there you need at least a certain amount of German to survive… If you do speak german though there are some interesting BA and MA programmes as well as a small portfolio of executive/professional courses.
Frankfurt School of Finance & Management is the city’s main business school and has the most international profile of programmes. It is the only internationally accredited (AACSB/EQUIS) business school in the city but also has official university status in germany. A key difference is that the school is private though, so unlike the two above, you have to pay for your education. There are 2 (out of 7) BSc programmes in English and 7 (out of 9) Masters in English. The good news is that this includes both an EMBA and an MBA in english. The classes look very international and have quite a good reputation. Frankfurt School is well known in Germany for finance, but it is beginning to get a good reputation among business schools as well overseas thanks to its Financial Times rankings. A good one to watch!
The last one is the University for Music and Performing Arts. The student body (900 total) is fairly international coming from over 50 countries, but with only a couple of degrees in English, German language is key. The good thing is that the German requirement is not as high as for other places :-). But keep an eye on their events section as they host over 200 performances a year and are open to the public. There is also a special programme for gifted youngsters to be taught in either English or German but the entry level is very high for this.