How to Calculate GPA

GPA is the sum of (credits × grade points) for every course, divided by your total credits. It's not a simple average of your letter grades, since a 4-credit course counts for more than a 1-credit course. This guide walks through the formula, a worked example, and the mistakes that throw the number off.

This is for anyone who wants to check a GPA by hand, understand why a transcript shows a number that doesn't match a simple grade average, or figure out what grade they need in a remaining course. If you just want the number, skip to the GPA calculator and enter your courses directly.

The formula

GPA = (sum of credits × grade points) ÷ total credits

Every course contributes two numbers: its grade point (a number tied to your letter grade) and its credit hours (how much weight the course carries). Multiply the two for each course, add all of those products together, then divide by the total credits. That's the whole calculation. The complexity people run into isn't the math, it's remembering to weight by credits instead of just averaging the grade points directly.

Worked example

Say you took three courses in a semester:

• Writing, 3 credits, grade A (4.0)
• Statistics, 4 credits, grade B+ (3.3)
• History, 3 credits, grade A- (3.7)

Multiply each grade point by its credits: (3 × 4.0) + (4 × 3.3) + (3 × 3.7) = 12 + 13.2 + 11.1 = 36.3. Divide by total credits (3 + 4 + 3 = 10): 36.3 ÷ 10 = 3.63 GPA.

Notice that a simple average of 4.0, 3.3, and 3.7 would give you 3.67, close but not the same as 3.63. The difference is small here because the credit values are close together. Put a 1-credit lab with an A next to a 5-credit lecture with a C, and the gap between a simple average and a real GPA gets a lot wider, which is exactly why schools weight by credits in the first place.

Standard grade point scale

Most US institutions use some version of a 4.0 scale, though the exact plus/minus values vary by school. This is the most common version:

Some schools don't use plus/minus grading at all, some cap GPA at 5.0 for weighted honors tracks, and a few use a 10 or 20-point local scale instead. The University of Kansas registrar and the University of South Carolina registrar both publish their scales publicly if you want to see how two real schools define theirs. If you need an official number, always use the grade point values your own school assigns, not a generic table you found online, this one included.

Grades that don't count

Not every mark on a transcript feeds into GPA. Pass/fail (P/NP), satisfactory/unsatisfactory (S/U), incomplete (I), audit (AUD), and withdrawal (W) grades are commonly excluded from the calculation, even though the credits may still count toward your degree. Include only graded, GPA-bearing courses in the formula, or you'll get a number that doesn't match your official transcript.

Common mistakes

• Averaging grade points directly instead of weighting by credits. Fine when every course has the same credit value, wrong the moment they don't.
• Including pass/fail or audited courses in the total.
• Using a grade point scale from a different school. A B+ is worth 3.3 at some schools and 3.33 or 3.5 at others.
• Forgetting a retaken course. If your school replaces the old grade instead of averaging both attempts, leaving the old grade in the calculation inflates or deflates the result.

Cumulative GPA and combining terms

To combine a new term with your existing GPA, treat your prior GPA as its own weighted entry: multiply it by your total prior credits, add the new term's weighted points, then divide by your combined total credits. This comes up often enough that it's worth its own walkthrough. See how to calculate cumulative GPA for the full method with an example.

Solving for a target GPA

Sometimes the question isn't "what's my GPA," it's "what do I need to hit a 3.5." Work the formula backward: multiply your target GPA by your total credits (current plus remaining) to get the total grade points you need, subtract the grade points you've already earned, then divide by your remaining credits to see the average grade you need going forward.

Example: you have 60 credits at a 3.2 GPA (192 grade points) and 15 credits left, aiming for a 3.5 cumulative (75 total credits × 3.5 = 262.5 points needed). You need 262.5 − 192 = 70.5 more points from 15 credits, an average of 4.7. Since 4.7 is above the maximum on a standard 4.0 scale, hitting a 3.5 from here isn't mathematically possible in one term, only over more terms. Running this kind of check before you plan a semester avoids setting a goal the math won't support.

Weighted, unweighted, and international scales

A weighted GPA adds extra points, often 0.5 or 1.0, for honors, AP, or IB courses, so it can exceed 4.0. An unweighted GPA treats every course the same regardless of difficulty and typically caps at 4.0. Neither is more "correct"; they answer different questions, and colleges often recalculate applicants onto one common scale anyway. See weighted vs unweighted GPA for a side-by-side example.

Outside the US, many countries use entirely different scales: the UK uses degree classifications, much of Europe uses the ECTS A-F system, and India commonly uses a 10-point CGPA. None of these convert to a 4.0 GPA with perfect precision, since the underlying grading philosophy differs. If you need an estimate, see what is the ECTS grading system or the ECTS to GPA tool.

To run this calculation on your own courses without doing the arithmetic by hand, use the GPA calculator.