DIY Cost Tools
Grade Calculator
EDUCATION CALCULATOR
Turn points earned into a percentage and common letter grade, then see how many additional points reach a target.
How it works
Enter earned points, available points, optional extra credit, and a target percentage. The letter grade uses a clearly stated common scale.
Formula
Percentage = (earned points + extra credit) ÷ possible points × 100. Points short = target rate × possible points − current earned points.
Worked example
438 points out of 500 is 87.6%, a B+ on the displayed common scale. Reaching 90% requires 12 additional points if the possible total stays 500.
Important limits
- Teachers and schools use different grade boundaries, weighting, curving, dropping, and extra-credit rules.
- The points-short result assumes the denominator does not change.
- Use the course syllabus or gradebook as the authoritative policy.
Frequently asked questions
Can the percentage exceed 100%?
Yes, if extra credit raises earned points above possible points.
Does this calculate weighted categories?
No. It is a points-based calculator; category-weighted courses need the official course method.
Sources and review notes
The arithmetic is transparent, but the letter mapping is only a common example. Confirm grading rules with the instructor or institution. Last reviewed September 29, 2026.