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Semester Grade Calculator

Find your semester grade from two quarter grades and a final exam, or the score you need on the final to reach your goal.

Level: Grades 6–7

Printable worksheet

Semester Grade Calculator

Know the answer you need? Pick an input to work backward.

Inputs
What do you want to find?

Your syllabus usually lists this. The two quarters share the rest equally.

Result

Semester grade

89%

With quarters of 88% and 92% and a final of 85%, your semester grade is 89%.

Letter on a 90/80/70/60 scale
B
Quarter average
90%

See the step-by-step solution ↓

Step-by-step solution

  1. Average the two quarters, because they count equally

    (88+92)2=90

  2. The quarters carry the 80% of the grade that the final doesn't, so take that share of the average

    90×80%=72

  3. The final is worth 20% of the grade, so take that share of your exam score

    85×20%=17

  4. Add the two parts to get your semester grade

    72+17=89%

Test yourself

20 quick questions built from this calculator's formula: work out results, predict what happens when an input changes, and work backward from an answer. Every answer comes with the working.

What this calculator does

Find out what your semester grade will be, or what you need on the final to get the grade you want. Many high schools split a semester into two quarters plus a final exam. This page is built for exactly that setup.

Enter your two quarter grades and how much the final counts. You'll see your semester grade and a letter, or the exam score you need. Don't worry about the math. Every step is shown with your own numbers.

Where it's used

Why this math matters outside the classroom:

  • Planning for finals. A student with a 90 average and a 20% final sees that 72 points are already earned and an exam of 90 keeps an A.
  • Choosing study time. A student with two finals spends more time on the class that needs an 87.5 than the one that needs a 60.
  • Parent conferences. A parent checks a report card by averaging quarters of 75 and 80 to get 77.5 before a meeting with a teacher.
  • Teacher gradebooks. A teacher double-checks a gradebook by taking 80% of a 90 average and adding 20% of an 85 exam to confirm 89.

How to use it

  1. Choose whether you want your semester grade or the score you need on the final.
  2. Enter your first and second quarter grades as percents.
  3. Enter the final exam weight from your syllabus. A common weight is 20%.
  4. Enter your exam score, or the semester grade you're aiming for, and read the result.

What the inputs mean

First quarter grade
Use the percent from your report card. If your school only gives letters, ask your teacher for the percent behind the letter.
Final exam weight
This is the share of the semester grade that comes from the final. If it's 20%, the two quarters share the other 80%, so each counts for 40%.

Formula and method

quarter average = (Q1 + Q2) ÷ 2
semester grade = quarter average × (100% − w) + exam × w
exam needed = (goal − quarter average × (100% − w)) ÷ w

Q1 and Q2 are your quarter grades, and w is the final exam's weight. A semester grade is a weighted average, which means some parts count more than others.

The second formula adds the two parts: what your quarters earned and what the exam earned. The third runs that backward. It starts with your goal, takes away what the quarters already earned, and asks what the exam must supply.

Worked example

You earned 88% and 92% in your two quarters. The final is worth 20%, and you scored 85% on it.

  1. Average the quarters: (88 + 92) ÷ 2 = 90.
  2. The quarters count for 80%, so 90 × 80% = 72.
  3. The final counts for 20%, so 85 × 20% = 17.
  4. Add the parts: 72 + 17 = 89.

Result: Your semester grade is 89%, which is a B on a 90/80/70/60 scale. To finish with 90%, you'd need a 90 on the final.

Understanding the result

A needed score over 100% means the goal is out of reach without extra credit. Try a lower goal to see what is possible.

A needed score of 0 or less means your quarters have already secured that goal. You still want to take the final, since skipping it may carry its own penalty.

The final matters most when your quarters sit close to a cutoff. At a 20% weight, each point on the exam moves your semester grade by 0.2 points.

Assumptions and limitations

  • The two quarters count equally and share everything the final doesn't.
  • Letters use the common scale of 90 for an A, 80 for a B, 70 for a C and 60 for a D.
  • Grades aren't rounded. Your school may round 89.5 up to 90, or it may not.
  • It doesn't fit schools that weight quarters unequally. Use the general grade calculator for those.
  • Plus and minus letters aren't shown, because cutoffs vary between schools.
  • Your teacher's gradebook always decides your official grade.

Frequently asked questions

How much is each quarter worth?

With a 20% final, each quarter is worth 40% of the semester. That's half of the 80% left after the final.

What if there's no final exam?

Then your semester grade is the average of your two quarters. Add them and divide by 2. The final exam field needs a weight above 0, so do that sum by hand.

Can I enter grades over 100%?

Yes, up to 120%. That leaves room for extra credit in a quarter or on the exam.

How do I use letter grades?

Swap each letter for a percent near the middle of its range, such as 85 for a B. The result will be an estimate, since a letter covers a range of scores.

How this calculator is checked

Method: Standard weighted average arithmetic. The calculation is covered by automated tests with known reference values and edge cases. Last updated 2026-10-31. Found a problem? Tell us.

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