Your grade point average (GPA) is a single number that summarizes your grades across many classes. Colleges, scholarship committees and some employers look at it, so it helps to know exactly how it is calculated rather than relying on a black box. This guide shows the standard method step by step, then covers weighted GPA, cumulative GPA, and the situations that trip people up.
One important caveat up front: schools set their own rules. The method below is the common U.S. approach, but your school's handbook or registrar has the final say on scales, weights and rounding.
Step 1: Convert each letter grade to grade points
Most U.S. high schools and colleges use a 4.0 scale. A common version looks like this:
| Letter | Grade points |
|---|---|
| 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 schools give an A+ 4.3, some do not use pluses and minuses at all, and some use slightly different values. Check your school's scale. For the percent ranges behind each letter, see our letter grade scale.
Step 2: Multiply grade points by credit hours
Not every class counts equally. A class worth 4 credits has more influence than one worth 1 credit. To account for that, multiply each class's grade points by its credit hours. The result is often called quality points.
Step 3: Add up quality points and credits, then divide
- GPA = total quality points ÷ total credit hours
That is the whole formula. Here is a worked semester:
| Class | Grade | Points | Credits | Quality points |
|---|---|---|---|---|
| Biology | A− | 3.7 | 4 | 14.8 |
| English | B+ | 3.3 | 3 | 9.9 |
| Calculus | B | 3.0 | 4 | 12.0 |
| History | A | 4.0 | 3 | 12.0 |
| PE | A | 4.0 | 1 | 4.0 |
| Total | 15 | 52.7 |
GPA = 52.7 ÷ 15 ≈ 3.51.
If every class had the same credits, you could simply average the grade points. Credit hours are what make it a weighted average in the mathematical sense.
Check your weighted grade or what you need on the final — free, in your browser.
Open the free grade calculator →Calculating cumulative GPA
Your cumulative GPA covers every term, not just the current one. The mistake most people make is averaging their semester GPAs. That only works if every semester had the same number of credits.
The correct way is to add all quality points from all terms and divide by all credits:
- Fall: 45.0 quality points over 15 credits (GPA 3.00)
- Spring: 52.7 quality points over 15 credits (GPA 3.51)
- Cumulative: (45.0 + 52.7) ÷ (15 + 15) = 97.7 ÷ 30 ≈ 3.26
If spring had been 18 credits instead, the cumulative figure would lean more toward spring, which is exactly why you use totals rather than averaging the two GPAs.
Weighted vs unweighted GPA
In high school, you will often see two GPAs:
- Unweighted GPA uses the standard 4.0 scale for every class, regardless of difficulty.
- Weighted GPA adds extra points for advanced classes such as Honors, AP, IB or dual enrollment. A common approach adds 0.5 for Honors and 1.0 for AP/IB, so an A in an AP class might count as 5.0.
The method is identical; only the grade points change. If your school adds 1.0 for AP, an AP class with a B counts as 4.0 instead of 3.0 in the weighted calculation.
Policies vary a lot. Some schools cap weighting, some only weight certain grades, and many colleges recalculate GPA using their own rules when reviewing applications. Treat a weighted GPA as useful within your school and the unweighted version as the easier one to compare.