How to Calculate Your GPA Step by Step

Your grade point average (GPA) is a weighted average: classes with more credit hours count for more. Here's how to work it out on the common US 4.0 scale.

Step 1: Convert each grade to points

A typical scale looks like this (schools vary slightly, so check yours):

• 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, F = 0

Some schools give an A+ 4.0 and others 4.3.

Step 2: Multiply by credit hours

For each class, multiply the grade points by the class's credit hours. The result is called quality points.

Step 3: Divide by total credits

A worked example

• Biology, 4 credits, B+: 3.3 × 4 = 13.2
• English, 3 credits, A: 4.0 × 3 = 12.0
• History, 3 credits, B: 3.0 × 3 = 9.0
• Art, 2 credits, A−: 3.7 × 2 = 7.4

Total quality points = 41.6 and total credits = 12, so the GPA is 41.6 ÷ 12 = 3.47.

Cumulative GPA

To combine semesters, don't average the semester GPAs. Add up all quality points from every semester and divide by all credit hours. A 12-credit semester at 3.0 and an 18-credit semester at 3.8 give (36 + 68.4) ÷ 30 = 3.48, not 3.4.

Weighted vs. unweighted

Many high schools add extra points for honors or AP classes (often 0.5 or 1.0), producing a "weighted" GPA above 4.0. Colleges often recalculate GPAs their own way, so keep both numbers handy.

Course grades first

Your letter grade in each class usually comes from a weighted mix of assignments, quizzes and exams. If homework is worth 20% and you average 90% on it, it contributes 18 points to your course percentage. Knowing the weights also tells you what score you need on the final.