The standard values
A = 4.0, A− = 3.7, B+ = 3.3, B = 3.0, B− = 2.7, C+ = 2.3, C = 2.0, C− = 1.7, D+ = 1.3, D = 1.0, D− = 0.7, and F = 0.0. These grade points are what get averaged (weighted by credits) into your GPA.
How plus and minus grades work
A plus adds roughly 0.3 and a minus subtracts roughly 0.3 from the base grade. Not every school uses plus/minus — some use whole-letter grades only, where a B is simply 3.0 with no B+ or B−.
Common variations
A few schools award 4.33 for an A+ (though the reported GPA is often still capped at 4.0). Others use .67/.33 increments (A− = 3.67) or half-point systems. Always confirm your school's exact scale — our university pages list many of them.