# Weighted Average Calculator Calculate a weighted average from paired values and weights, with contribution and normalized weight details > Canonical page: https://elysiatools.com/en/tools/weighted-average-calculator - **Category:** Math & Numbers - **Keywords:** weighted average, weighted mean, weights, grade average, statistics, GPA ## Overview Calculate a weighted average from values and matching weights. weighted average = sum(value x weight) / sum(weight) Use it for grades, portfolio returns, survey scores, priority scoring, and any dataset where each value has a different importance. ## Inputs - **Values** (textarea): e.g. 90, 85, 95 - **Weights** (textarea): e.g. 0.3, 0.2, 0.5 - **Decimal Places** (number) - **Normalize Weights In Output** (checkbox) ## 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 - Students and teachers calculating final course grades based on syllabus weightings (e.g., 20% homework, 30% midterm, 50% final). - Financial analysts computing the weighted average cost of capital (WACC) or overall portfolio returns based on capital allocation. - Product managers using weighted scoring models to prioritize feature development based on impact, effort, and strategic alignment. ## Frequently asked questions ### 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. 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