Methodology and Assumptions

Last reviewed 2026-10-22.

GPA

Grade points: A+ and A are 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, F 0. This is a common convention, not a standard. Some schools treat A+ as 4.3.
GPA = sum of (grade points x credits) / sum of credits.
Weighted GPA adds 0.5 for honors and 1.0 for AP, IB or dual-credit courses, only to passing grades. Schools use different values.
Cumulative GPA = (current GPA x current credits + term GPA x term credits) / (current credits + term credits).

Weighted grade = sum of (score x weight) / sum of weights, so weights do not need to add to 100.
Needed final score = (goal - current x (1 - final weight)) / final weight.
Letter grades use a common 10-point scale with plus and minus: A+ 97, A 93, A- 90, B+ 87, B 83, B- 80, C+ 77, C 73, C- 70, D+ 67, D 63, D- 60. Teachers differ.

Percent of = X / 100 x Y. X as a percent of Y = X / Y x 100. Percent change = (new - old) / old x 100.

Results show two decimals and are rounded half up. Grade points are kept in exact tenths during the calculation, so rounding does not build up.

Curves, dropped scores, extra-credit policies, grade replacement for retaken courses and school-specific rounding.

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