How do US grad schools interpret international GPAs? I am an international student looking to apply for a PhD in mathematics in mainly the USA. My current university uses a 10 point scale for GPA but most of the universities I've seen, in the US seem to use a 4 point scale, and they rarely provide a conversion scale to convert a 10 point GPA to a 4 point one. 
Some people suggest dividing my current GPA by 10/4=2.5 to get my 4 scale GPA but as my masters' GPA is 7.6/10 (not great, I know) this formula makes it 7.6/2.5= 3.04 and so just barely above the minimum required for the most places. And according to it, I can never get into a PhD program.

As disheartening as it is, IMO this does not seem to be a correct way to interpret an international GPA. After all, the universities abroad don't know how were the classes taught, their contents and how difficult/easy it was to get good grades is in different unis.

At my university, it is really difficult to get good grade. One can get one of the following grades, A, B, C, or a D and it is incredibly difficult to get an A, most of the times only one or two people would get it, and so slim chances of getting most of As. My transcripts are filled with mostly Bs, (and I know I worked really hard for them), a few As and Cs and unfortunately one D (worst decision ever to take that class, it's not related to what I want to study in grad school, the instructor gave one grade to each of the students who took the class). Also, my last two years of coursework was very heavy (at least for me), we'll have 5-6 courses (all math) each semester, and I struggled a lot with my time management throughout this. Combine it with some anxiety and overthinking issues, and you have a bad GPA as a result.

So, my questions are- 

1) How do grad schools in the US interpret international GPAs?

2) Would it be okay to address the reasons for my low GPA in SOP)personal statement briefly, like in a line or two? If so, how should I subtly go about doing it? I don't want to make an excuse and of course, don't want to blame others.

3) Should I just give up on applying for PhDs then and focus more on the masters program, say in some Canadian universities? 

(I should mention that in the name of 'research experience' I only have a bunch of reading projects/ independent studies and a Masters' thesis. My university didn't offer courses and a supervisor directly in my area of interest and so I don't have much background in it and that's why I don't feel confident to directly apply for a PhD elsewhere like in Europe or Canada)
1) How do grad schools in the US interpret international GPAs?


Exactly the same way we interpret domestic GPAs!  We rely on our previous experience with applicants from your institution and our (Google-enhanced) knowledge of the content and rigor of your degree program.  After all, there's no universal interpretation of grades even within a particular country.

And as others have already said, your GPA is only one component of your application, and not necessarily even the most important.


  2) Would it be okay to address the reasons for my low GPA in SOP)personal statement briefly, like in a line or two? If so, how should I subtly go about doing it? I don't want to make an excuse and of course, don't want to blame others.


You're assuming your GPA is low enough to require explaining, but that assumption is based on a naive numerical conversion, which really isn't appropriate.  Whether your grades are actually "low" is a good question for the people who will write you letters, who presumably have some experience with the type of PhD programs you're applying to.  (Otherwise, how would they know what they're recommending you for?)  In particular: Would your GPA prevent you from getting a PhD at your current institution?

However, I do think you need to explain your lack of formal research experience ("My university didn't offer courses and a supervisor directly in my area of interest"), both as justification for your current research record and as motivation for pursuing a PhD elsewhere.


  3) Should I just give up on applying for PhDs then and focus more on the masters program, say in some Canadian universities?


No!  Never throw away opportunities until you're sure you don't have them!  If you know you want a PhD, and you believe you are qualified for a PhD, and enough people are willing to write you strong recommendation letters for PhD programs, then you should apply to PhD programs!  But if you're still worried about your chances of admission, you should also apply to some masters programs as backup.