A Grade Point Average (GPA) is a numerical summary used to evaluate a student’s academic performance. The 4.0 scale is the primary method utilized by educational institutions across the United States to standardize this evaluation. Converting letter grades into a numerical value often causes confusion, especially when dealing with grades that include a plus or minus modifier, such as the A-.
The Standard Letter-to-GPA Scale
The most widely accepted standard for converting letter grades to a Grade Point Average assigns a value of 3.7 to an A- grade. This conversion is used by the majority of high schools and universities when calculating an unweighted GPA on the traditional 4.0 scale. The unweighted scale reflects academic achievement without factoring in the difficulty of the course material.
The standard scale assigns 4.0 for an A, 3.3 for a B+, 3.0 for a B, and 2.7 for a B-. Grades below a C are assigned 1.7 for a C-, 1.3 for a D+, and 1.0 for a D.
Why Conversions Vary
The confusion regarding whether an A- is a 3.5 or a 3.7 stems from two primary factors: institutional discretion and the use of weighted scales. Some individual school districts or older grading systems may opt for a simplified scale that does not use the standard plus/minus modifiers. In these cases, an A- might be grouped with a B+ and assigned a 3.5, or the school may simply not recognize the A- grade at all.
The second major variation involves the difference between unweighted and weighted GPAs. A weighted GPA is used for advanced coursework, such as Advanced Placement (AP), International Baccalaureate (IB), or Honors classes. These systems often add an extra point to the standard numerical value to acknowledge the increased rigor of the curriculum.
For example, an A- in a standard class is 3.7, but that same A- in an AP course would often be calculated as a 4.7 on a 5.0 scale. This adjustment allows colleges to compare students who take different levels of courses fairly.
How to Calculate Your Unweighted GPA
Calculating an unweighted GPA requires three straightforward steps once the standard numerical values are known. The first step involves converting every letter grade received into its corresponding numerical point value, using 3.7 for any A- grade.
The second step is to sum all of the numerical grade points together. If a student earned an A (4.0), a B+ (3.3), and an A- (3.7), the total sum would be 11.0. The final step is to divide that total sum by the total number of classes taken.
Using the example of 11.0 divided by three classes, the resulting unweighted GPA is 3.67.