How the final grade calculator works
Your class grade is a blend of two parts: everything before the final, and the final itself. If the final is worth 20%, your current grade counts for the other 80%.
needed = (target − current × (1 − weight)) ÷ weight
Weight is the final's share as a decimal, so 20% is 0.2. The answer is the percent you need on the exam. Above 100% means you can't reach the target without extra credit. Zero or below means you've already got it.
Point-based classes. If your teacher adds up points instead of using weights, the final's weight is its points divided by all points in the class. A 200-point final in a 1,000-point class is worth 20%. Your current grade is points earned so far divided by points possible so far.
Letter grades on this page use a common scale: 93 and up is an A, 90 to 92 an A-, 87 to 89 a B+, and so on down to F below 60. Your syllabus may set different cutoffs.
Worked example
You have an 85% going into the final. The final is worth 20%. You want a 90%.
Your current grade covers 80% of the class: 85 × 0.8 = 68 points.
You need 90 − 68 = 22 more points from the final, which is worth 20: 22 ÷ 0.2 = 110%.
That's out of reach. A perfect final gets you 68 + 20 = 88%. To finish with an 85%, you'd need (85 − 68) ÷ 0.2 = 85% on the final.
Common questions
What if I need more than 100% on the final?
Then the target isn’t reachable on the final alone. Check the "With 100% on the final" line for the best grade you can still get. Ask your teacher about extra credit, dropped scores or retakes, since any of those change the math.
What if the answer is zero or negative?
You’ve already secured that grade. Even a 0 on the final keeps you at or above your target, as long as the final is the only thing left.
How do I find how much my final is worth?
Look in the syllabus for a grading breakdown, like "Final exam 20%". If the class uses points, divide the final’s points by the total points for the term.
Does my teacher round up?
Some do and some don’t. An 89.5% might become a 90 in one class and stay a B+ in another. This calculator doesn’t round, so if you aim for exactly the cutoff, you’re safe either way.
What if my class has other work left besides the final?
This calculator assumes the final is the last graded item. If you still have homework or a project due, use the grade calculator with every category and its weight.