The best replacement for letter grade is gpa.

The best alternatives to letter grade are rated as following:
★★★★★  gpa
★★★★  number grade
★★★  percentage
★★  pass fail
★★  percent
★  numerical grade
  grade point average
  pass no pass

Your alternative for letter grade is not listed? Suggest!
Speaking about letter grade, one probably shouldn't forget about number grade.

Other search terms related to letter grade and their ratings are:
★★★★★ number grade
You have in mind a companion for letter grade and it is not yet here? Propose!



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letter grade
gpa
number grade