High School GPA Calculator

Background.

This high school GPA calculator answers the question most 9th-12th graders actually have: "what's my GPA, based on the grades I've got?" — without first requiring you to look up a credit-hours table. Type in your letter grades, separated by commas, and leave the credit-hours box blank if you don't know it or don't need it; the calculator treats every class as equal weight by default, which is exactly right for the overwhelming majority of U.S. high school schedules where a year-long course is worth one Carnegie unit (the standard credit-hour definition the Carnegie Foundation set in 1906 and that most American high schools still use today).

The calculator uses the unweighted 4.0 scale — A=4.0, A-=3.7, B+=3.3, B=3.0, and so on down to F=0.0 — the same base scale College Board's own GPA guidance publishes. It never adds a bonus for AP, IB, or honors courses; that is a separate, more specific calculation with its own separate tool (the weighted-gpa-calculator on this site), because whether and how much of a bonus to add is not standardized nationally and is a judgment call each school district makes independently.

If some of your classes carry different credit weights — a common example is a semester-only health or PE class worth 0.5 credit sitting alongside full-year 1.0-credit classes — you can enter a credits list to get a more precise, credit-weighted GPA. When you do, the calculator reports two numbers side by side: the credit-weighted gpa and a simpleAverageGpa that ignores credit hours entirely and just averages the grade points. Comparing the two tells you exactly how much the credit-weighting is changing your number. If you leave credits blank, the two numbers are identical, because every class defaults to the same weight of 1.0 — which is precisely the behavior most high-school students expect when they think of GPA as "just the average of my grades."

Because every U.S. high school district sets its own grading policy — some use a straight-letter scale with no plus/minus modifiers at all, and the federal NCES's own transcript-study methodology defaults to the simpler A=4/B=3/C=2/D=1/F=0 scale rather than the plus/minus version — treat the number this calculator returns as a close estimate of the standard national convention, not a guaranteed match to your school's own transcript. If you need the exact number your registrar will print, check your school's published grading handbook for its specific point table, and use this calculator to sanity-check the arithmetic once you know it.

What is high school gpa calculator?

A high school GPA is a grade point average computed from letter grades on the standard, unweighted 4.0 scale (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). The GPA is technically a credit-weighted mean: each course's grade points are multiplied by its credit hours, those products are summed, and the total is divided by total credit hours attempted. In practice, most U.S. high school classes carry the same credit weight — one Carnegie unit per year-long course, per the Carnegie Foundation's original 1906 definition — so this calculator lets you leave the credits field blank and defaults every class to equal weight, which produces the same result as a plain arithmetic average of your grade points. If your schedule mixes full-year and semester-only classes, you can supply an explicit credits list for a more precise, credit-weighted figure.

How to use this calculator.

1. 01List every class's letter grade, separated by commas, e.g. "A, B+, A-, B".
2. 02If every class in your schedule carries the same credit weight (the common case), leave the credit-hours field blank.
3. 03If some classes are semester-only or otherwise carry a different credit weight, enter a comma-separated list of credit hours in the same order as your grades, e.g. "1, 1, 0.5, 1".
4. 04Read the gpa result. If you left credits blank, it will match the simpleAverageGpa exactly.
5. 05Compare gpa to simpleAverageGpa if you did enter credits — the gap between them shows how much the credit-weighting is affecting your number.
6. 06Double-check your school's exact grading scale in its handbook if you need a number that matches your official transcript precisely.

The formula.

The formula is the standard credit-weighted mean:

gpa = Σ(base(gradeᵢ) × creditsᵢ) / Σ creditsᵢ

where base(grade) is the plain 4.0-scale value of the letter grade, with no AP/Honors bonus applied. When the credits field is left blank, creditsᵢ = 1.0 for every class, which makes the formula collapse to a plain arithmetic mean of the grade points — exactly the simpleAverageGpa value reported alongside it. The two figures diverge only once a real, non-uniform credits list is supplied: simpleAverageGpa = Σ base(gradeᵢ) / n always ignores credit hours, while gpa always uses them. Because credit hours only ever appear as positive multipliers in both the numerator and denominator, the credit-weighted gpa is always a value between the highest and lowest individual grade point in the list — it can never fall outside that range, regardless of how the credits are distributed.

A worked example.

Frequently asked questions.

References& sources.

1. [1]Carnegie Foundation for the Advancement of Teaching — "What Is the Carnegie Unit?" Definition of the standard one-credit, roughly 120-hour, year-long high school course used as the default equal-weight assumption in this calculator.
2. [2]College Board — BigFuture, "How to Calculate Your GPA on a 4.0 Scale." Source of the unweighted 4.0-scale letter-grade conversion table used in this calculator.
3. [3]U.S. Department of Education, National Center for Education Statistics (NCES) — Handbook of Survey Methods, High School Transcript Studies (HSTS). Federal methodology for GPA computation and the simpler four-point (no plus/minus) scale used in national transcript studies.