Hey there @Arin!
What @ericbomfim is correct, but if you want an even easier method, I've linked CollegeVine's GPA Converter below.
Hope this helps!
https://blog.collegevine.com/how-to-convert-your-gpa-to-a-4-0-scale
Figure out what your percentage is, by taking your GPA and dividing it by 5. Then, take that percentage and multiply it by 4!
To keep this community safe and supportive:
I personally just looked up a chart of the grades on a 4.0 scale and converted it by hand myself because whenever I tried a converter or any of the other ways my converted gpa would be extremely low. When I calculated it by hand it came back as what I expected and then I just asked my counselor if the gpa I hand converted was correct or not.