How to Calculate GPA: The Complete Step-by-Step Guide

Your grade point average is a single number that summarises everything you have done academically. Calculating it from scratch takes four steps and a small amount of arithmetic. Once you understand the recipe, every variant — weighted, unweighted, semester, cumulative — is just a different way of mixing the same ingredients.

Step 1 — Convert each letter grade to GPA points

The standard US 4.0 scale assigns the following point values:

Letter	GPA points	Percentage band
A+	4.0 (or 4.33 at some schools)	97–100%
A	4.0	93–96%
A-	3.7	90–92%
B+	3.3	87–89%
B	3.0	83–86%
B-	2.7	80–82%
C+	2.3	77–79%
C	2.0	73–76%
C-	1.7	70–72%
D+	1.3	67–69%
D	1.0	63–66%
D-	0.7	60–62%
F	0.0	Below 60%

If your school does not use plus/minus modifiers, every A is 4.0, every B is 3.0, and so on. Some universities (Canadian and a few US grad programs) cap A+ at 4.33; most cap it at 4.0.

Step 2 — Multiply each grade by its credits

The number of credits a course is worth tells you how heavily it counts. Most US high school courses are 1 credit (year-long) or 0.5 credits (semester-long). College courses are usually 3 or 4 credit hours; lab sciences are often 4; one-credit seminars exist too.

Multiplying gives you quality points — the contribution of that course to your total.

Step 3 — Add up the quality points

Sum the quality points across every course on the transcript you are calculating.

Step 4 — Divide by total credits

Take the total quality points and divide by the total credits attempted. Round to two decimals.

A complete worked example

Here is a one-semester transcript:

Course	Grade	GPA pts	Credits	Quality pts
Calculus II	A-	3.7	4	14.8
General Chemistry	B+	3.3	4	13.2
English Composition	A	4.0	3	12.0
World History	B	3.0	3	9.0
Spanish I	A-	3.7	3	11.1
Totals	—	—	17	60.1

GPA = 60.1 ÷ 17 = 3.54

That is the unweighted semester GPA on the standard 4.0 scale. Our GPA Calculator performs this exact math, including for percentage inputs.

Cumulative GPA — combining multiple terms

To compute a cumulative GPA, sum the quality points across every term you have completed and divide by the total credits across every term. Equivalently, you can take a credit-weighted average of your semester GPAs:

cumulative = Σ(semester GPA × semester credits) / Σ(all credits)

Our Cumulative GPA Calculator does this with one click.

Weighted GPA — adding boosts for harder courses

A weighted GPA adds a bonus to grades earned in advanced courses. The most common system in US high schools:

Regular courses: +0
Honors courses: +0.5
AP, IB, or dual-enrollment college courses: +1.0

An A in a regular class is 4.0; an A in an Honors class is 4.5; an A in an AP class is 5.0. The weighted formula is the same as the unweighted formula, with the boost added to each course\u2019s GPA points before multiplication. Use our Weighted GPA Calculator for the math.

Edge cases that trip people up

Withdraw (W) — does not count in the GPA. The credit drops out of both numerator and denominator.
Pass / fail — does not count either way. The credit counts toward graduation but the grade does not enter the average.
Incomplete (I) — usually treated as F until resolved. Once a final grade is submitted, that grade replaces the I.
Repeat / replacement — at schools with grade-replacement policies, a retake replaces the original grade in the GPA calculation. Both grades remain on the transcript for transparency.
Audit (AU) — does not count for GPA or credits. The course attendance shows on the transcript but neither the credit nor the grade is included.

Summary

Convert grades to 4.0-scale points.
Multiply by credits → quality points.
Sum quality points.
Divide by total credits.

Or, if you would rather not pull out a calculator: type your grades into our GPA Calculator and get the same result in three seconds.