Your transcript says one number and a web calculator says another, and the difference is almost never a typo. It is the scale, the credit weighting, or the rounding. We document our own GPA calculator the only reliable way, by reading the code line by line, so you can predict its output before you click.
The 11-Grade Scale in This Calculator
The grade dropdown offers exactly 11 options. Each stores a fixed point value.
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
Two absences matter. There is no A+, so if your school awards 4.3 for it, results here will read low. There is also no D- or F variants, and nothing between D and F, which matches the common US convention but not every policy.
The Weighted Average Formula
The calculation is one loop. For each course it accumulates credit times grade into totalPoints and credit into totalCredits, then divides.
gpa = totalPoints / totalCredits
The result prints with toFixed(2), two decimal places. That is a display cap, so a true value of 3.428571 shows as 3.43 and a true 3.153846 shows as 3.15.
Two Worked Examples
Example one. You earned an A in a 3-credit course and a B in a 4-credit course. Quality points are 4.0 times 3 plus 3.0 times 4, which is 24. Credits are 7. The tool divides 24 by 7, gets 3.428571, and displays 3.43.
Example two. Four courses, an A at 3 credits, a B+ at 3 credits, a C at 4 credits, and an A- at 3 credits. Quality points are 12 plus 9.9 plus 8 plus 11.1, which is 41. Credits are 13. The tool divides 41 by 13, gets 3.153846, and displays 3.15.
Both examples were evaluated against the deployed arithmetic, not estimated.
Why Credit Weighting Dominates
The formula makes course weight the deciding factor in planning. A 4-credit B pulls a 3-credit A down more than a 1-credit course can pull anything anywhere, because every course enters the average multiplied by its credits.
Use this rule when you plan a term. Rank your courses by credits before you rank them by expected difficulty, and protect the high-credit ones first. A one-point grade slip in a 4-credit course moves a 13-credit semester by about 0.31, the same slip in a 1-credit course moves it by about 0.08.
Edge Cases in the Code
Three behaviors are visible in the implementation and worth knowing.
1. A cleared credit field counts as zero. The field converts input with Number, so an emptied box becomes 0 credits, and that course stops contributing to both sums without any warning.
2. An empty list prints nothing. Remove every row and press calculate, and the code sets the result to null and shows no number at all. It does not show zero, which is correct behavior, zero would be a false GPA.
3. Nothing persists. The course list lives in component state. Refresh the page and your rows are gone, so copy your inputs elsewhere if the session matters.
The credit field declares min 1 and max 10, but typed values outside that range still reach the calculation, because the attributes constrain the spinners rather than the stored value.
What This Calculator Does Not Do
- No A+ option, so 4.3-scale schools read low here.
- No weighted high school scale, no 5.0 AP boost.
- No percentage or letter conversion, you enter letter grades only.
- No semester versus cumulative split, one list computes one average.
- No save, no export, no history.
For anything on that list, use your registrar's official tool, because that is the number that appears on your transcript.
Steps for a Number You Can Trust
1. Enter each course with its exact credit hours from your transcript, not rounded values.
2. Pick the letter grade you actually received, remembering A+ maps to A here.
3. Confirm no credit field is blank or zero unless you mean it to be.
4. Press calculate and read the two-decimal result.
5. Compare against your transcript, and if they differ by more than 0.01, check for an A+ or a credit entry error before blaming either tool.
Checklist
- [ ] Your school maps grades the same way this 11-entry table does.
- [ ] Credit hours match the transcript exactly.
- [ ] No credit field was left empty.
- [ ] You treated the result as two decimals, not exact.
- [ ] You used the registrar's tool for official numbers.
Compute your own weighted average on the [GPA calculator page](/en/gpa-calculator). If your result differs from your transcript's, send us both numbers plus your school's scale, and we will trace exactly where the formulas diverge.
