If your school hands back grades as letters. A, B+, C-, and so on, figuring out your actual GPA takes more than just averaging them. Here's exactly how it works, and how to do it in seconds instead of by hand.
Step 1: Convert each letter grade to grade points
Every letter grade maps to a point value on a 4.0 scale. The most common US scale looks like this: A/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 = 0.0.
Some institutions round slightly differently (for example, treating A- as 3.67 instead of 3.7), so it's worth checking your school's official chart if you need an exact figure for a transcript.
Step 2: Multiply by credit hours
A GPA isn't a plain average of your grades, it's weighted by how many credit hours each course carries. Multiply each course's grade points by its credit hours to get that course's "quality points."
Step 3: Add everything up and divide
Add up the quality points from every course, then divide by the total number of credit hours. That final number is your GPA.
Skip the manual math
Use the free GPA Calculator →, just enter each course's grade and credit hours, and it does steps 1 through 3 instantly.A quick worked example
Say you took three courses: an A in a 3-credit class, a B+ in a 4-credit class, and an A- in a 3-credit class. That's (4.0 × 3) + (3.3 × 4) + (3.7 × 3) = 12 + 13.2 + 11.1 = 36.3 quality points, across 10 total credits. 36.3 ÷ 10 = a 3.63 GPA.
Common mistakes to avoid
- Forgetting to weight by credit hours, a straight average of letter grades gives a different (usually wrong) number.
- Mixing up your school's specific point scale with a generic one, especially for grades like A- or B-.
- Not including a course at all because it feels like it "doesn't count", pass/fail and audited courses usually don't factor in, but check your school's policy rather than assuming.
What about CGPA?
CGPA (Cumulative GPA) uses the exact same formula, just applied across every semester you've completed instead of one term. If you're tracking it over time, keep a running list of every course, grade, and credit hour, and run the same calculation across the whole set.
Need to double-check a percentage-based grade instead? The Percentage Calculator handles marks-to-percentage conversions too.