How to Calculate GPA: Weighted, Unweighted and Cumulative

GPA is a credit-weighted average on the 4.0 scale. The worked example below comes out at 3.40 unweighted and 3.67 weighted, and raising a 3.0 to a 3.5 after 60 credits takes another 60 credits of straight A grades.

The Formula

Grade point average is a credit-weighted average. Turn each grade into points on the 4.0 scale, multiply by the course’s credits, add those up, and divide by the total credits. The standard conversion, published by the National Scholarship Providers Association, is:

Weighted GPA adds points for harder courses before averaging. The NSPA’s weighted tables top out at 4.5 for honors and 5.0 for AP, the common +0.5 and +1.0 bonuses. Schools differ in both the scale and the bonuses, and the College Board notes that colleges may recalculate your GPA with their own criteria, so check your school’s method.

A Worked Example

Five 1-credit courses, A- in honors English, B+ in Algebra II, B in AP Biology, A in US History, B- in Spanish, plus a half-credit A in Art. Unweighted: (3.7 + 3.3 + 3.0 + 4.0 + 2.7 + 0.5 × 4.0) / 5.5 = 18.7 / 5.5 = 3.40. Weighted, with +0.5 for honors and +1.0 for AP: 20.2 / 5.5 = 3.67. Our GPA Calculator showed exactly 3.40 and 3.67 for these courses.

How Hard It Is to Raise a GPA

Because GPA is an average over all your credits, every credit you have already earned anchors it. If you have c credits at GPA g, the number of credits of straight 4.0 grades needed to reach a target t is c × (t − g) / (4 − t):

The pattern is the useful part: the higher the target and the more credits behind you, the more it takes. Moving from 3.0 to 3.5 with 60 credits takes another 60 credits of nothing but A grades. Early terms matter most, and a realistic plan is to set a target for the credits you have left; the calculator’s “What do I need?” box does that sum and tells you when a target cannot be reached.

Your Grade in One Course

Inside a single class, a weighted syllabus works like a mini GPA: multiply each category’s score by its weight and divide by the weights graded so far. Homework 92% (20%), quizzes 85% (20%), a 78% midterm (25%) and a 94% project (15%) give 6,900 / 80 = 86.25%, a B on the standard bands, before the final is graded. In a points course you simply divide points earned by points possible. The Grade Calculator does both and leaves ungraded work out instead of counting it as zero.

The Score You Need on a Final

Course grades work the same way inside one class: the final exam is a fixed share of the grade, so the score you need is (target − current grade × (1 − w)) / w, where w is the final’s share. With 86% now and a final worth 25%, an 88 needs 94% on the final, while a 90 would need 102%, so the best reachable grade is 89.5%. The Final Grade Calculator does this, or works out your current grade from weighted categories first.

Common Mistakes

Averaging the grade points without the credits (a half-credit elective counts as much as a full course that way); rounding up (a 3.996 is not a 4.0 on most transcripts, which is why our calculator cuts to two decimals); and mixing scales, for example using a weighted GPA where a college asks for unweighted.

Frequently Asked Questions

Published Oct 14, 2026 by Derek Giordano