How to calculate your GPA in 5 minutes

Your GPA looks like a single number, but it's quietly doing a lot of work behind the scenes — translating dozens of letter grades into one digit that scholarships, transfer applications, and graduate programs all rely on. Here's the calculation broken down, plus the most common mistakes to avoid.

The two scales that matter

Most US and Canadian schools use a 4.0 scale, where an A = 4.0, B = 3.0, C = 2.0, D = 1.0, and F = 0.0. The UK and Australia use percentage or classification systems, but if you're applying to a North American university they'll usually convert. Two flavors matter:

• Unweighted GPA — every class counts the same regardless of difficulty.
• Weighted GPA — honors, AP, and IB classes get a +1.0 (or +0.5) bonus on the standard scale.

The 4-step calculation

1. Convert each letter grade to a grade point value (A = 4.0, A− = 3.7, B+ = 3.3, etc.).
2. Multiply each grade point by the course's credit hours.
3. Add up the quality points (grade × credits) for every class.
4. Divide that total by the total credit hours you've taken.

The formula in one line: GPA = Σ(grade_point × credits) ÷ Σ(credits)

A quick example

Say you took four 3-credit courses this term and earned an A, A−, B+, and B. Your quality points are:

1. A × 3 = 4.0 × 3 = 12.0
2. A− × 3 = 3.7 × 3 = 11.1
3. B+ × 3 = 3.3 × 3 = 9.9
4. B × 3 = 3.0 × 3 = 9.0

Total quality points = 42.0. Total credits = 12. GPA = 42.0 ÷ 12 = 3.50.

Common mistakes to avoid

• Forgetting that credit hours (not the class count) are the weighting factor.
• Mixing up your school's specific scale — some use +/− grades, others only whole letters.
• Including pass/fail or transfer credits where they shouldn't be counted.
• Applying the weighted bonus to every honors-track class instead of the qualifying ones.

Pro tip: always compute your GPA twice — once with weights, once without. Schools, scholarships, and employers each pick a different version, and knowing both keeps you from getting blindsided.

Skip the manual math

Once you've done it by hand once or twice for the practice, there's no reason to keep doing it manually every semester. Our GPA Calculator handles unweighted, weighted, and country-specific scales in one form — drop in your courses and credits and you'll see your GPA update live.