Add your subjects or assignments with their scores and weights to calculate your weighted average, letter grade, and 4.0-scale GPA. Also find out what score you need on remaining work to hit a target grade.
A simple average treats every assignment as equally important, but real courses rarely work that way — a final exam is almost always meant to count for more than a single homework assignment, and a weighted average is the standard mathematical tool for reflecting that intentional difference in importance. Without weighting, a student who aces every small homework assignment but struggles on major exams could end up with a misleadingly high average that doesn't reflect how the course is actually graded — weighting corrects for this by making each component's contribution to the final grade proportional to how much the instructor has decided it should count.
The formula is straightforward once broken down: multiply each assignment's score by its weight, add up all of those products, then divide by the sum of all the weights. Dividing by the total weight (rather than the number of assignments) is what makes the calculation correct even when your weights don't sum to a round number like 100 — it automatically normalizes the result to a proper percentage regardless of how many assignments you've entered or how much of the total course weight they represent so far. This is exactly why the calculation still produces a meaningful, accurate current average even partway through a course, before every graded component has been entered.
A percentage-based weighted average and a letter grade both describe the exact same underlying performance, just using different scales — a percentage gives fine-grained precision (87.3% versus 87.4%), while a letter grade buckets that precision into broader categories (both would simply be a 'B'). GPA takes this bucketing one step further, converting each letter grade into a single number on a 4-point scale specifically designed to be averaged across many different courses with different grading scales and difficulty levels, producing one overall academic performance figure. Each conversion step (percentage to letter, letter to GPA point) necessarily loses some precision, which is a deliberate tradeoff — GPA exists specifically to make performance comparable and averageable across dissimilar courses, not to preserve every decimal point of a single course's percentage grade.
The 'what grade do I need' calculation is simply the weighted average formula solved in reverse — instead of computing your average from known scores, it computes the one unknown score (on your remaining weight) that would produce a specific target average, given everything you've already earned. This is exactly the kind of calculation students do informally before a final exam ('I have an 82% going into the final, which is worth 30% of my grade — what do I need to get an 90% overall?'), formalized into an exact, reliable formula instead of rough mental math. Knowing precisely what score you need — and specifically whether your target is even still mathematically achievable — is far more useful for planning your remaining study effort than a vague sense of 'I should probably do well on the final.'
This calculator is useful at any point in a course, not just after every grade is in. Early on, entering just your first few assignments shows your current standing and highlights whether you're on track. Midway through, the 'what grade do I need' feature lets you set a realistic goal for your final exam or remaining assignments based on exactly where you currently stand, rather than guessing. And at the very end, once every component's weight has been entered and sums to 100%, the calculator gives you your true final course grade and GPA contribution — all using the same consistent weighted average math throughout.
Grade Calculator handles weighted averages, letter grades, and GPA for a single course. These related calculators cover other everyday math you might need alongside it.