Grade Calculator

The Grade Calculator turns a list of assignment scores into a single course grade, and answers the question every student asks near the end of a term: what do I need on the final? It runs two calculations. The weighted grade mode combines scores that each carry a weight, such as homework worth 20%, a midterm worth 30%, and a final worth 50%, into one percentage and its matching letter grade. The final grade mode takes your grade so far, the weight of the exam still ahead, and the grade you are aiming for, and returns the exact score you need to sit for.

Grades are almost never a plain average. A syllabus assigns different weights to quizzes, labs, participation, and exams, so a 95% on a 5% quiz moves your grade far less than a 70% on a 40% final. Working that out by hand is error-prone, and getting it wrong means either panicking over a grade that is actually safe or coasting on one that is slipping. The calculator applies the weights for you and shows how much each piece contributes in percentage points, so you can see which assignment is really driving your grade.

The weights do not have to add up to 100. Partway through a semester you can enter only the graded work and the tool divides by the total weight so far, giving an honest running average rather than a number dragged down by ungraded items counted as zero. Extra-credit scores above 100 are accepted, and the result maps to the standard United States letter scale with pluses and minuses, plus its grade-point value on the 4.0 scale.

Everything runs in your browser in plain JavaScript. No scores are uploaded, there is no sign-up, and the calculator keeps working with no connection once the page has loaded, so you can plan a study schedule on a laptop or check a grade on your phone between classes without your marks ever leaving your device.