| Letter | Course grade | Needed on the final |
|---|
Letter-grade scale: common US 10-point scale, but your school may differ (edit the cutoffs)
Anything below the D cutoff is an F. Letters are based on the result rounded to two decimals.
About this final grade calculator
This final grade calculator answers the question students ask most at the end of a term: what grade do I need on my final? It also works as a weighted grade calculator for classes graded by category, and as a points calculator for classes graded by total points. Every result updates as you type.
How to use it
- What do I need on the final? Enter your current grade, the final exam's weight from your syllabus and the course grade you want. The table underneath shows the score needed for every letter.
- Weighted categories. Add a row for each category with its score as a percentage and its weight. Leave out categories you have not been graded in yet. Then click "Use as current grade in final mode" to carry the result over, along with the weight that is still left.
- Points. Enter the points you earned and the points possible for each assignment.
- Check the letter scale. Open the scale panel and change the cutoffs to match your syllabus.
The final exam formula
Your course grade is a blend of the work already graded and the final. With the final worth w (30% = 0.30):
course grade = current × (1 − w) + final × w
Solving for the final score gives the formula the calculator uses:
required = (target − current × (1 − w)) ÷ w
Two limits follow from it. Scoring 0% on the final leaves you with current × (1 − w), and scoring 100% gives current × (1 − w) + 100 × w. A target above the second number is impossible without extra credit, and a target at or below the first is already secured.
Worked example
The calculator opens with a current grade of 83.36%, a final worth 30% and a target of 85%:
(85 − 83.36 × 0.70) ÷ 0.30 = (85 − 58.352) ÷ 0.30 = 88.83% on the final.
The range line shows that a 0% final would leave you at 58.35% and a perfect final would lift you to 88.35%. The letter table gives the score needed for each grade: 105.49% for an A, which is out of reach, 72.16% for a B, 38.83% for a C and 5.49% for a D.
That 83.36% comes from the weighted categories mode, which opens with homework at 88% (weight 20), a midterm at 79% (weight 25) and other graded work at 84% (weight 25): (88 × 20 + 79 × 25 + 84 × 25) ÷ 70 = 5,835 ÷ 70 = 83.36%, a B.
When the target is impossible or already secured
- Impossible. With 80% going in and a final worth 20%, reaching 90% needs (90 − 80 × 0.8) ÷ 0.2 = 130%. The best you can finish with is 84%, so the calculator says the target is out of reach and shows that ceiling.
- Already secured. With 95% going in and a final worth 10%, a target of 80% needs (80 − 95 × 0.9) ÷ 0.1 = −55%. Even a zero on the final leaves you at 85.5%.
- A final worth 100%. Then 1 − w is zero, your current grade drops out, and the score you need equals your target.
How the weighted grade calculator works
A weighted grade multiplies each category's score by its weight, adds the results and divides by the total weight. When the weights add up to 100, that last step changes nothing. When they don't, the calculator still divides by their actual total, which is called normalizing, and shows a warning with the share each category ends up with. With the default rows, the weights add up to 70, so homework counts 20 ÷ 70 = 28.57% and each of the other two counts 35.71%. That is exactly what you want when the missing 30 is a final you haven't taken yet. If the weights are short because you forgot a category, the warning is your cue to add it.
Points-based classes
In a points-based class, your grade is total points earned ÷ total points possible, and averaging the percentages gives the wrong answer. The points mode opens with a quiz scored 9/10 (90%) and a test scored 60/100 (60%). Averaging the two percentages gives 75%, but the points grade is 69 ÷ 110 = 62.73%, because the test is worth ten times as many points. Entering each percentage in weighted mode with its points possible as the weight gives the same 62.73%. For a single score such as 43 out of 50, the Percentage Calculator gives the percentage directly.
Letter grades
Many US schools use a 10-point scale: A from 90%, B from 80%, C from 70%, D from 60% and F below that. It is common, but not universal. Some schools set an A at 93%, add plus and minus grades, or round 89.5% up. The calculator starts on the 10-point scale, and you can change any cutoff to match your syllabus.
Common mistakes
- Treating points as weights. If the syllabus says homework is worth 10% of the grade, use 10 as its weight, even if the homework adds up to 200 points. Points only act as weights in a points-based class.
- Mixing weight formats. 20/25/30 and 0.20/0.25/0.30 give the same result, because the calculator divides by the total. Mixing the two in one list, such as 20, 25 and 0.3, does not.
- Counting an ungraded category as zero. A blank category is not a zero. Leave it out until you have a score.
- Forgetting missing work. A missing assignment usually does count as zero, so enter it.
- Rounding too early. Keep two decimals until the end. Rounding 83.357% to 83% before the final formula changes the answer from 88.83% to 89.67%.
For a step-by-step version with more examples, read how to calculate your final grade. To describe how much a grade moved, see percentage vs percentage points.
Frequently asked questions
Use required = (target − current × (1 − w)) ÷ w, where w is the final's weight as a decimal. With 83.36% going in and a final worth 30%, reaching 85% needs (85 − 83.36 × 0.7) ÷ 0.3, which is 88.83% on the final.
It means you can’t reach that target with the final exam alone unless extra credit is available. For example, with 80% going in and a final worth 20%, reaching 90% needs (90 − 80 × 0.8) ÷ 0.2, which is 130%. The most you can finish with is 84%. Try a lower target, or ask your instructor whether other work can still raise your grade.
Each category's score is multiplied by its weight, those results are added, and the total is divided by the sum of the weights. Homework at 88% (weight 20), a midterm at 79% (weight 25) and other work at 84% (weight 25) give 5,835 ÷ 70 = 83.36%.
The weighted grade calculator divides by the total you entered, which normalizes the weights, and shows a warning with each category's actual share. That is right when the missing weight belongs to work not graded yet, such as the final. If you left a graded category out, add it.
Divide the total points you earned by the total points possible and multiply by 100. A quiz scored 9/10 and a test scored 60/100 give 69 ÷ 110 = 62.73%, not the 75% you get by averaging the two percentages. The Points mode does this for you.
It starts on a common US 10-point scale: A from 90%, B from 80%, C from 70%, D from 60% and F below 60%. Schools differ, with plus and minus grades, a 93% A or different rounding, so open the scale panel and set the cutoffs from your syllabus.
You can approximate extra credit by entering a score over 100 for that category, which will pull the weighted average above what it would otherwise be. Check with your instructor, since not all grading systems allow a category to exceed 100%.