๐ Weighted Average Calculator
Enter multiple values along with a weight for each one, and this tool automatically calculates the weighted average. Unlike a simple average, weights let values with greater importance or credit hours count for more, making this useful for GPA calculations or combining multiple metrics with different levels of significance.
How to use
- Enter value/weight pairs.
- Use "Add row" to add more entries (up to 10 rows).
- The weighted average is calculated automatically.
How the calculation works
A weighted average gives each value a weight; values with larger weights pull the average more. Weighted average = (valueโ ร weightโ + valueโ ร weightโ + โฆ) รท (weightโ + weightโ + โฆ) If all the weights are equal, the result is the ordinary (arithmetic) mean. You can enter up to 10 values and weights; rows with a weight of 0 or less, or non-numeric entries, are left out. Useful for GPAs (grades weighted by credits), test scores with different point values, or the average cost of shares bought in several lots.
Worked example
Values 90 (weight 2), 80 (weight 3), 70 (weight 1) (90 ร 2 + 80 ร 3 + 70 ร 1) รท (2 + 3 + 1) = (180 + 240 + 70) รท 6 = 490 รท 6 โ 81.67 The plain average would be (90 + 80 + 70) รท 3 = 80; the weighted one is higher because 80 and 90 carry more weight.
Things to be aware of
- Weights can be proportions (0.2, 0.3), counts or credits; they do not need to add up to 1 or 100.
- For the average cost of shares, use each purchase price as a value and the number of shares as its weight.
- For course grades, use each component's share of the final mark as its weight (for example midterm 30%, final 70%).
FAQ
How is this different from a simple average?
A simple average treats every value equally, while a weighted average lets values with a larger weight influence the result more.
Can I enter 0 or a negative weight?
Only positive weights are valid โ rows with a weight of 0 or less are excluded from the calculation.
Can this be used for GPA calculations?
Yes, enter each course's grade point as the "value" and its credit hours as the "weight" to calculate a GPA.