Weighted Average Calculator
Calculate a weighted average from up to four value and weight pairs, ideal for grades where assessments carry different weightings.
Your results
Calculation breakdown
- Weighted average
- Σ(value × weight) ÷ Σ(weight)
Worked example
An assignment worth 40%, a mid-term worth 30% and a final worth 20% scoring 70, 85 and 60 give (70×40 + 85×30 + 60×20) ÷ 90 = 74.4.
Assumptions
- Set a weight to 0 to exclude that value/weight pair.
- Weights don't need to add exactly to 100 as long as they're proportionally correct.
How this calculator works
This calculator multiplies each value by its weight, sums the results, and divides by the total weight to find the weighted average. It's commonly used for course grades where different assessments contribute different percentages to a final mark.
Frequently asked questions
What if my weights don't add to 100?
The calculator normalises using the total of the weights you enter, so they don't need to add exactly to 100 as long as they're proportionally correct.
Can I leave a value/weight pair blank?
Set the weight to zero for any pair you're not using and it will be excluded from the calculation.
How is this different from a simple average?
A simple average treats every value equally, while a weighted average gives more influence to values with a higher weight.