GPA Calculator

Background.

This GPA calculator converts a list of letter grades and credit hours into a grade point average on the standard U.S. 4.0 scale — the same scale used by virtually every American college transcript, every Common App entry, every law-school LSAC report, and every employer that asks for your GPA on a résumé. Enter your courses as a JSON array of grade-and-credit pairs (the default example shows the format), and the calculator returns your GPA rounded to two decimal places, the total credit hours you entered, and the total quality points — the three numbers a registrar would print on an official transcript line.

The math itself is short: GPA equals the sum of (grade points × credits) divided by the sum of credits. The reason a GPA calculator exists as its own tool is that the inputs are unintuitive in three specific ways.

First, the U.S. 4.0 scale is not linear in percentage terms — an A is worth 4.0, an A- is worth 3.7, a B+ is worth 3.3, and the gaps between adjacent letters are not uniform. Most schools use the +/- variant of the scale defined by the College Board and adopted by institutions like MIT and Harvard, but a meaningful minority use a 'straight letter' scale where A, B, C, D, F are the only options and an A- is recorded as a 4.0. Both conventions are common; which one you use depends on the school printing your transcript. Second, credit hours are the weighting factor, not the number of courses. A 4-credit physics course counts roughly 33% more toward your GPA than a 3-credit elective at the same letter grade. Third, a 'cumulative' GPA spans every term you have ever attempted, while a 'term GPA' covers only one semester or quarter — they are computed the same way but on different course sets, and the two diverge as soon as you have one strong or weak term that pulls the running average.

The widget treats every course you paste in as an attempted, graded course. Withdrawals (W), incompletes (I), pass/no-credit (P/NC), and audits (AU) are explicitly excluded from GPA calculations on most U.S. transcripts and should be omitted from your input. The same goes for transfer credits at schools that grant credit but do not transfer the grade, which is the policy at most selective universities including MIT ("Transferred subjects are recorded with credit but no grade and are not included in any GPA calculation," per the MIT Registrar).

What the calculator deliberately does not try to do is reconstruct the weighted-vs-unweighted GPA distinction used by U.S. high schools — that is a separate calculation explained below, because high-school GPAs commonly assign 5.0 to an A in an AP, IB, or honors course rather than the 4.0 a college transcript would record.

If you are a high-school student calculating a GPA for college admissions, this tool will give you the unweighted figure that selective admissions offices reconstruct anyway (the National Association for College Admission Counseling — NACAC — reports that admissions readers routinely 'recalculate' submitted GPAs to a common scale to remove the inflation produced by inconsistent weighting policies). Whether you are projecting a term GPA before finals, sanity-checking your transcript before you submit it to a graduate school application, or figuring out exactly what grade you need in your last semester to clear a 3.5 cumulative threshold for an honors designation, the calculator is here to do the arithmetic so you can spend your time on the strategy.

What is gpa calculator?

Grade point average (GPA) is the credit-hour-weighted mean of the grade points earned in a defined set of courses. On the standard U.S. 4.0 scale, an A is worth 4.0 grade points, an A- is 3.7, a B+ is 3.3, a B is 3.0, and so on down to F at 0.0. To compute a GPA you multiply each course's grade-point value by its credit hours (yielding 'quality points'), sum the quality points across all courses, then divide by the total credit hours attempted. Courses graded pass/fail, withdrawn from, or transferred without a grade are typically excluded from the calculation. A 'term GPA' applies the formula to a single semester or quarter's courses; a 'cumulative GPA' applies it to every graded course on the transcript. The scale, the inclusion rules, and the +/- convention are set by each institution's registrar — the version implemented here mirrors the +/- scale published by the MIT Registrar and used in substantially identical form by Harvard FAS and most U.S. four-year colleges.

How to use this calculator.

1. 01List every course you want to include in the GPA you are calculating — typically a single term for a 'term GPA' or every graded course you have ever taken for a 'cumulative GPA'.
2. 02For each course, look up the letter grade exactly as it appears on your transcript. Valid values are: A, A-, B+, B, B-, C+, C, C-, D+, D, D-, F.
3. 03Find each course's credit hours (sometimes called 'units' or 'credits'). A typical lecture course is 3 or 4 credits; a lab section might be 1 credit.
4. 04Format the list as a JSON array of objects, one per course. Example: [{"grade":"A-","credits":3},{"grade":"B","credits":4},{"grade":"A","credits":3}].
5. 05Paste the array into the courses field and read the GPA result — it is rounded to two decimal places, which matches transcript convention.
6. 06Exclude any course graded W (withdrawn), I (incomplete), P/NC or S/U (pass/no-credit), or AU (audit) — these do not carry grade points and should not appear in the array.
7. 07To project a future GPA, add hypothetical courses with the grade you expect to earn; the calculator treats them identically to real ones.

The formula.

The grade-point-average formula is a credit-weighted mean:

GPA = Σ(gradePointsᵢ × creditsᵢ) / Σ(creditsᵢ)

where gradePointsᵢ is the 4.0-scale value of the letter grade in course i (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, D- = 0.7, F = 0.0) and creditsᵢ is the credit-hour weight of that course. The numerator is what U.S. registrars call the 'quality points' or 'total grade points' on a transcript; the denominator is the total credit hours attempted (not earned — an F still contributes its credit hours to the denominator, which is why a single failing grade can pull a GPA down sharply). The +/- mapping is the one published by the MIT Registrar and used in substantively identical form by Harvard FAS; some schools omit A+ (capping at 4.0) and some that include A+ assign it 4.0 rather than 4.3, so an A+ does not actually push a GPA above 4.0 on most transcripts. The arithmetic is performed in Decimal.js to avoid IEEE-754 floating-point drift — important when chaining many course terms and rounding the result to two decimal places at the end. Note what the formula does not do: it does not 'weight' courses by their honors, AP, or IB designation. That is the unweighted-versus-weighted distinction explained in the FAQ below; this calculator returns the unweighted GPA that college admissions offices typically recompute anyway.

A worked example.

Frequently asked questions.

References& sources.

1. [1]MIT Registrar's Office — Explanation of Grades. Official grade-point values on the 4.0 scale, including the +/- mapping, and the exclusion rules for P/DR/OX grades from GPA calculation.
2. [2]Harvard Faculty of Arts and Sciences (FAS) Registrar — Grading System. Authoritative reference for letter-grade-to-grade-point conversion at Harvard and treatment of SAT/UNS grades.
3. [3]College Board — Calculating Your GPA. Plain-language explanation of weighted versus unweighted GPA and the absence of a national standard for the weighting bump assigned to honors/AP/IB courses.
4. [4]National Association for College Admission Counseling (NACAC) — State of College Admission. Annual survey documenting the weight admissions readers place on overall high school GPA and grades in college-prep courses, and the practice of recalculating submitted GPAs to a common scale.
5. [5]U.S. Department of Education, Institute of Education Sciences — National Center for Education Statistics (NCES). Aggregate data on U.S. high school GPA distributions and trends in grading over time.
6. [6]World Education Services (WES) — Grade Conversion Guide. Widely cited reference for converting international grading systems (UK, German, Indian, French, etc.) to the U.S. 4.0 letter-grade scale prior to GPA calculation.