How to Calculate a Weighted Grade

If a course says homework is 20%, quizzes 10% and the midterm 30%, a simple average of your scores ignores those percentages. Suppose you score 100 on a quiz worth 5% and 60 on an exam worth 50%. The plain average is 80, but the weighted result is far lower because the exam counts ten times as much. Always use the weights from your syllabus.

Weighted grade = Σ(score × weight) ÷ Σ(weight). Multiply each score by its weight, add the results, and divide by the total weight of the work graded so far. With homework 90% (weight 20), a quiz 80/100 (weight 10) and a midterm 70% (weight 30): 90 × 20 + 80 × 10 + 70 × 30 = 4,700, divided by 60 = 78.33%. That is a C+ on the 60% of the course graded so far.

The question every student asks: what must I score on the remaining work to reach a target? Needed average = (target × total weight − points earned) ÷ weight remaining. Here points earned are 47 (on a 100-point scale), the course is out of 100 and 40 is still to come. To finish at 80%: (80 − 47) ÷ 0.40 = 82.5%. If the answer is above 100, the target is not reachable without extra credit; a target of 99% would need 130% (above 100% — only possible with extra credit).

If you only know your current overall grade c and the final’s weight w (as a decimal), the score needed for a target is (target − c × (1 − w)) ÷ w. A current 78% with a final worth 30% and a target of 80% needs 84.66666667%. The grade calculator has both modes.

• Enter points as fractions (42/50) to avoid conversion mistakes.
• Check how your instructor handles dropped scores, extra credit and rounding.
• Recalculate after every graded item to keep your target realistic.
• Convert the result to grade points with the GPA calculator if you need your term GPA.