# GPA calculator

> GPA calculator: credit-weighted grade point average on the 4.0 scale from letter grades, plus percentage-to-GPA and CBSE CGPA-to-percentage conversions.

交互版本：https://www.calcopenly.com/zh/everyday/gpa-calculator
主题：日常计算器

GPA is a credit-weighted average. Each course's grade points (A = 4.0, A− = 3.7, B+ = 3.3 and so on down to D− = 0.7 and F = 0 on the University of Michigan LSA scale) are multiplied by its credits, added up and divided by the total credits.

The default four courses (A− for 3 credits, B+ for 4, A for 3 and C for 2) earn 40.3 grade points over 12 credits, a GPA of 3.36. Two other modes convert a percentage to the 4.0 scale with the College Board's table (88% is a B, worth 3.0) and a 10-point CGPA to a percentage with CBSE's rule of 9.5 × CGPA.

Schools differ: some count A+ as 4.3 (a switch under More options), some add weight for honors and AP courses, and many universities publish their own CGPA formula. Check the key on your transcript before quoting the number.

## 输入

- **Start from** (选项：Courses, 百分比, 10-point CGPA)
- **Courses: grade, credits**: One course per line, optionally with a name first: “Calculus, B+, 4”. Grade points like 3.7 also work.
- **Count A+ as 4.3**
- **Percentage grade**
- **CGPA (out of 10)**

## 结果

- GPA (4.0 scale) — 主要结果
- Credits
- Grade points earned
- Letter grade
- Percentage (CBSE, 9.5 × CGPA)

## 公式

$$
\begin{gathered}\text{GPA} = \frac{\sum \text{points}_i \times \text{credits}_i}{\sum \text{credits}_i} \\ \%_{\text{CBSE}} = 9.5 \times \text{CGPA}\end{gathered}
$$

## 计算示例

### Four courses

- Start from: Courses
- Courses: grade, credits: A-, 3 / B+, 4 / A, 3 / C, 2
- **GPA (4.0 scale): 3.36**
- **Credits: 12**
- **Grade points earned: 40.3**
- 核验来源：Python decimal with U-M LSA points: (3.7×3 + 3.3×4 + 4×3 + 2×2)/12 = 40.3/12

### A+ as 4.3

- Start from: Courses
- Courses: grade, credits: A+, 3 / B, 3
- Count A+ as 4.3: 是
- **GPA (4.0 scale): 3.65**
- 核验来源：Hand calculation: (4.3×3 + 3×3)/6

### A+ as 4.0 (U-M LSA)

- Start from: Courses
- Courses: grade, credits: Chemistry A+ 3 / History B 3
- **GPA (4.0 scale): 3.50**
- 核验来源：U-M LSA: A+ = 4.0; (4×3 + 3×3)/6

### All failing grades

- Start from: Courses
- Courses: grade, credits: F, 3 / E, 4
- **GPA (4.0 scale): 0.00**
- **Credits: 7**
- 核验来源：U-M LSA: E = 0; College Board: F = 0

### 88% on the College Board scale

- Start from: 百分比
- Percentage grade: 88%
- **GPA (4.0 scale): 3.00**
- **Letter grade: B**
- 核验来源：College Board table: B 80–89 = 3.0

### Exactly 65%

- Start from: 百分比
- Percentage grade: 65%
- **GPA (4.0 scale): 1.00**
- **Letter grade: D**
- 核验来源：College Board table: F is below 65, so 65 is the lowest D (1.0)

## 常见问题

### How do you calculate GPA?

Multiply each course's grade points by its credits, add the products and divide by the total credits. A− (3.7) for 3 credits, B+ (3.3) for 4, A (4.0) for 3 and C (2.0) for 2 give 11.1 + 13.2 + 12 + 4 = 40.3 points over 12 credits, a GPA of 3.36. Each course counts in proportion to its credits.

### What letter grade is a 3.5 GPA?

A 3.5 sits halfway between a B+ (3.3) and an A− (3.7) on the plus/minus scale, so it is roughly an A−/B+ average: equal credits of A− and B+ average exactly 3.5. On the College Board's table without plus or minus grades, it falls between a B (3.0) and an A (4.0).

### How do you convert a percentage to a 4.0 GPA?

Use your school's own table where there is one. The College Board's general table gives 90–100% = A = 4.0, 80–89% = B = 3.0, 70–79% = C = 2.0, 66–69% = D = 1.0 and below 65% = F = 0.0, so 88% converts to 3.0. It has no plus or minus steps, so it is coarser than a transcript GPA.

### How do you convert CGPA to percentage?

For CBSE results, multiply the CGPA by 9.5. CBSE Circular 24 of 28 May 2010 gives the overall indicative percentage of marks as 9.5 × CGPA, so a CGPA of 8.2 is about 77.9% and 9.0 is 85.5%. Universities often set their own formula, so check the rule printed on your marksheet or in the university's regulations.

### Is an A+ worth 4.0 or 4.3?

It depends on the school. The University of Michigan's College of Literature, Science, and the Arts counts A+ as 4.0, the same as an A, while other schools award 4.3. Switch on "Count A+ as 4.3" to compare: an A+ and a B in two 3-credit courses average 3.5 under the first rule and 3.65 under the second.

### “GPA calculator”有多准确？

准确性取决于输入值和方法的假设。十进制运算使用50位有效数字，但估算、数值方法和源数据的精度可能较低；显示时的舍入并不能消除这些限制。 已按独立来源核验的计算示例：8。 例如，“Four courses”根据Python decimal with U-M LSA points: (3.7×3 + 3.3×4 + 4×3 + 2×2)/12 = 40.3/12进行核验。

### 这种方法出自哪里？

University of Michigan LSA — Grades and grading (A 4.0, A− 3.7, B+ 3.3 …); College Board BigFuture — How to convert your GPA to a 4.0 scale; CBSE Circular 24/2010 — indicative percentage = 9.5 × CGPA.

## 来源

- [University of Michigan LSA — Grades and grading (A 4.0, A− 3.7, B+ 3.3 …)](https://lsa.umich.edu/lsa/academics/lsa-academic-policies-and-procedures/grades-and-transcript-notations.html)
- [College Board BigFuture — How to convert your GPA to a 4.0 scale](https://bigfuture.collegeboard.org/plan-for-college/get-started/how-to-convert-gpa-4.0-scale)
- [CBSE Circular 24/2010 — indicative percentage = 9.5 × CGPA](https://www.cbse.gov.in/circulars/cir24-2010.pdf)