To find the score you need on a final exam, you need three numbers: your current grade, how much the final is worth and the overall grade you want. Then use this formula:
Score needed = (target grade − current grade × (1 − final weight)) ÷ final weight
Write the weight as a decimal — a final worth 30% is 0.3. The Grade Calculator does the whole calculation for you.
Example: what do I need to pass?
You have a 62% in the class, the final is worth 25%, and you need 60% overall to pass:
(60 − 62 × 0.75) ÷ 0.25 = (60 − 46.5) ÷ 0.25 = 54%
You need 54% on the final to pass the course.
Example: what do I need to get an A?
You have an 86%, the final is worth 30%, and an A starts at 90%:
(90 − 86 × 0.7) ÷ 0.3 = (90 − 60.2) ÷ 0.3 ≈ 99.3%
You’d need about 99% on the final — tough, but possible. If the answer comes out above 100%, the target isn’t reachable from the final alone.
Step 1: Work out your current grade
If your class uses weighted categories — for example homework 20%, quizzes 15%, midterm 25% — your current grade is a weighted average, not a simple average of every score:
- Multiply each category’s score by its weight.
- Add the results together.
- Divide by the total weight of the categories graded so far.
For example, 92% homework (20%), 84% quizzes (15%) and 78% midterm (25%) gives (92×20 + 84×15 + 78×25) ÷ 60 = 84.2%. Enter each category into the Grade Calculator and it shows your current grade as you type.
Step 2: Check the final’s weight
Look at your syllabus. Finals are usually worth 15–40% of the course grade. The bigger the weight, the more the final can move your grade — up or down.
Step 3: Decide your target
Common targets are the pass mark (often 60% or 70%) or the cut-off for a letter grade, such as 90% for an A or 80% for a B on a standard scale. Check your school’s grading scale, as cut-offs vary.
What does this do to my GPA?
Once you know the grade you’re aiming for, add your courses and letter grades to the GPA Calculator to see how it affects your semester and cumulative GPA. For quick percentage questions — like what 45 out of 60 is as a percentage — use the Percentage Calculator.
