Key Facts
- Category
- Math, Date & Finance
- Input Types
- textarea, number, checkbox
- Output Type
- json
- Sample Coverage
- 0
- API Ready
- Yes
Overview
The Weighted Average Calculator instantly computes the weighted mean of a dataset by combining your values with their corresponding weights. Whether you are calculating final grades, evaluating portfolio returns, or scoring survey results, this tool provides accurate results alongside detailed weight contributions and normalized percentages.
When to Use
- •Calculating final grades where assignments, midterms, and final exams have different percentage weightings.
- •Determining the overall return of an investment portfolio with varying asset allocations and position sizes.
- •Evaluating survey responses or priority scoring models where certain criteria carry more importance than others.
How It Works
- •Enter your dataset into the Values field, separating each number with a comma.
- •Input the corresponding importance of each value in the Weights field in the exact same order.
- •Adjust the decimal places and choose whether to normalize the weights in the output.
- •The tool multiplies each value by its weight, sums the results, and divides by the total weight to generate the final average.
Use Cases
Examples
1. Calculating a Final Course Grade
College Student- Background
- A student wants to know their final grade. Homework is worth 20%, the midterm is 30%, and the final exam is 50%.
- Problem
- Need to combine different assignment scores with their respective syllabus weights to find the final percentage.
- How to Use
- Enter the scores in the Values field and the percentages (as decimals or whole numbers) in the Weights field.
- Example Config
-
Values: 95, 82, 89 Weights: 0.2, 0.3, 0.5 - Outcome
- The tool calculates a final weighted average of 88.1, showing exactly how much the final exam contributed to the overall grade.
2. Evaluating Investment Portfolio Returns
Retail Investor- Background
- An investor holds three different stocks with varying amounts of capital invested in each. They want to calculate the overall portfolio return.
- Problem
- A simple average of the return percentages is inaccurate because the position sizes are different.
- How to Use
- Input the return percentages as Values and the dollar amounts invested as Weights.
- Example Config
-
Values: 12.5, -4.2, 8.0 Weights: 10000, 5000, 25000 - Outcome
- The calculator normalizes the dollar amounts into portfolio percentages and outputs the true weighted return of the entire portfolio.
Related Hubs
FAQ
What is the difference between a simple average and a weighted average?
A simple average treats all values equally, while a weighted average assigns a specific importance (weight) to each value, giving more significant items a greater impact on the final result.
Do my weights need to add up to 1 or 100?
No. The calculator automatically normalizes the weights by dividing the sum of the weighted values by the total sum of the weights you provide.
How should I format the values and weights?
Enter them as comma-separated numbers. Ensure that the number of items in the Values field exactly matches the number of items in the Weights field.
What does 'Normalize Weights In Output' mean?
This option converts your raw weights into proportional fractions or percentages in the detailed output, making it easier to see the relative contribution of each value to the whole.
Can I use decimals or negative numbers?
Yes, both the values and weights fields accept decimal numbers. Values can be negative (like investment losses), but weights should typically be positive numbers.