Every finals week, the same question gets typed a million different ways: what do I need on my final? This page answers it completely — the formula derived once, in plain language, and then the part students actually come for: the full grade table, current grade against final weight, showing the exact score needed for an A, a B and a C — including the cells where the honest answer is “not possible any more” and the cells where the grade is already safe. If you would rather just run your own numbers, the Final Exam Calculator does the same math instantly; this guide explains what it is doing and lets you read your answer straight off the grid.

The formula, derived once

Your course grade is a weighted average of two things: the work already done and the final exam. Call your current grade C, the final’s weight w (as a decimal, so 25% is 0.25) and the course grade you want T. The completed work contributes C × (1 − w) no matter what happens next — those are your banked points. The final must supply whatever is missing, and it can only supply it out of its own slice, so the missing amount is divided by w:

Score needed = (T − C × (1 − w)) ÷ w

One worked example, the most common set of numbers students bring to this question: current grade 88%, final worth 25%, target 90%. Banked points: 88 × 0.75 = 66.00. Missing: 90 − 66 = 24.00 points. Score needed: 24.00 ÷ 0.25 = 96.0%. That is all the formula ever does — bank what is finished, divide the gap by the weight. Everything else in this article is that one move, repeated across the grid.

Two consequences of the division are worth internalising before you read the tables. First, the smaller the weight, the more violent the division: at a 10% weight the gap is multiplied by ten, which is why light finals produce absurd required scores for ambitious targets. Second, the formula has no opinion about what is realistic — it will happily report 150%, and the sections after the tables explain how to read answers like that.

What you need for an A (90%)

Read your current grade down the left, the final’s weight across the top. “>100” means the target cannot be reached — the number of points the final would have to supply is more than the final contains.

Score needed on the final to finish at 90%, by current grade and final weight. Computed from (90 − C × (1 − w)) ÷ w, rounded to one decimal — the same formula and rounding the Final Exam Calculator uses.

The A table is the sobering one. An A survives a mediocre term only when the final is heavy: at a current grade of 85%, even a 40%-weighted final demands 97.5%, and anything lighter is already out of reach. At 90% current, the needed score is a flat 90.0% at every weight — hold your level and you hold the A. And at 95%, the table flips from defence to comfort: a 45.0% paper preserves the A when the final is worth just 10%.

What you need for a B (80%)

Score needed on the final to finish at 80%. “Safe” means your banked points already clear 80% — the final decides only how far above it you finish.

The B table is where most students actually live. The diagonal pattern is the formula showing through: when your current grade equals your target, the needed score equals both (80% current, 80% target, 80.0% needed at every weight) because you are simply being asked to hold your level. Drop one row down and the weight starts to matter more than the gap; reach the “Safe” cells — a 90% current grade with a 10% final has already banked 81.00 points — and the exam becomes a bonus round rather than a threat.

What you need for a C (70%)

Score needed on the final to finish at 70%. At ordinary weights, a C is less a target than a floor — most of this grid is already safe or nearly so.

Three students, one course, three different weeks

The tables reward a slow read, but a single weight — 25%, the most common final weight students bring to this question — shows the whole drama in three rows of one class. Amara holds 92%: she has banked 69.00 points, and an A (90%) asks a humane 84.0% of her — but notice that a 95% finish is already beyond her, since (95 − 69) ÷ 0.25 = 104 and her ceiling is 94.00%. Ben holds 76%: banked 57.00, and the B he wants (80%) demands 92.0% — a genuinely excellent paper — while the A is not a paper at all (112% required; his ceiling is 82.00%). Chloe holds 64%: banked 48.00, and her week is about floors, not ceilings — a C (70%) needs 88.0%, a 65% finish needs 68.0%, and even the 60% pass line needs a real 48.0% paper, because almost half her course grade is still unwritten. Same exam hall, same paper, three completely different assignments. That spread is why no honest answer to “what do I need?” exists without your own two numbers — and why the tables are organised by current grade first and target second.

Letter targets are percentages in disguise

One more reading skill the tables assume: your target is a percentage even when you think in letters, and schools draw the lines in different places. The grids above use the common 90 / 80 / 70 boundaries, but a school that sets its A line at 93% rewrites the top table brutally. The worked student — 88% current, 25% final, 66.00 banked — needs (93 − 66) ÷ 0.25 = 108.0% for that A: not reachable, full stop, where the 90-line school asked a steep but possible 96.0%. Plus-and-minus bands cut the other way: if you only need the bottom of the B+ band rather than the top of the A band, enter the bottom. Always aim the formula at the lowest score that earns the outcome you actually need — a prerequisite that demands “B or better” is an 80% target, not an 83% one, and the three saved points of target are worth twelve points of required score at a 25% weight.

“Not possible” and “already safe” are answers too

Two kinds of cells in the tables above deserve a kind reading, because students misread both. A >100 cell does not mean you failed the course; it means that one specific target is out of reach this term. The useful follow-up number is the highest grade still possible: banked points + the final’s full weight. A student at 70% with a 20% final tops out at 76.00% — the A and B are gone, but a C+ finish is entirely alive, and protecting it is a better use of the week than mourning the A. Conversely, a Safe cell does not mean the final does not matter: it still decides how far above the target you land, many courses require the final to be sat (and sometimes passed) regardless of the average, and scholarships or programme requirements may key off the final course grade rather than the letter you were protecting.

What do I need on my final to pass?

Passing is the same calculation with a lower target, and the pass mark is the one number in this article that is yours to supply: 60% and 65% are both common, and some programmes set it at 50% or 70%. Take the worked example from the formula section — current 88%, final worth 25%, so 66.00 banked points. Against a 60% pass mark the formula returns (60 − 66) ÷ 0.25 = −24: not a score at all, but the news that the course is passed on banked points alone. Against 65% it returns −4 — still safe. The students for whom passing is a live question are those whose banked points sit below the line: a current grade of 55% with a 30% final banks 38.50 points, and reaching 60% needs (60 − 38.50) ÷ 0.30 = 71.7% on the paper — a real target, and exactly the kind the calculator exists to size up honestly. When you calculate what I need on my final, you are really asking which of these three situations you are in: safe, striving, or out of reach. All three are better known than guessed.

And if you are wondering what grade do I need when the stakes are a scholarship line, a prerequisite minimum or a programme’s progression rule rather than a letter, the method does not change: put that threshold in as the target and read the table — or run it in the what do I need on my final calculator — the same way. What I need on my final is always one division away once the target is named.