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Weighted Average Calculator

To find a weighted average, multiply each value by its weight, add those results, then divide by the total of the weights. For example, homework at 92 (weight 25), quizzes at 84 (weight 25) and a final exam at 75 (weight 50) give a weighted average of 81.5. Enter your values and weights below to see the result and every step.

Weights can be percentages, credit hours, points or quantities

Calculate a weighted average

Enter each value and its weight. Weights can be percentages, credit hours or quantities, and they don’t need to add up to 100.

How to use the weighted average calculator

  1. Type each value (a score, grade point or price) and its weight (a percentage, credit hours or quantity) on its own row.
  2. Use “Add another value” for more rows, up to 20.
  3. Press Calculate to see the weighted average, the working table and how it compares with a simple average.

Weighted average formula

Weighted average = Σ(value × weight) ÷ Σ(weight)

Σ means “add them all up.” Because the formula divides by the total weight, the weights don’t need to add up to 100 or to 1.

How to calculate a weighted average

Here’s a course grade where homework is worth 25%, quizzes 25% and the final exam 50%.

  1. Multiply each score by its weight: 92 × 25 = 2,300; 84 × 25 = 2,100; 75 × 50 = 3,750.
  2. Add the results: 2,300 + 2,100 + 3,750 = 8,150.
  3. Add the weights: 25 + 25 + 50 = 100.
  4. Divide: 8,150 ÷ 100 = 81.5.

A simple average of the same scores would be 83.7, because it ignores that the final exam counts for half the grade.

Weighted average for GPA

GPA is a weighted average where each course’s grade points are weighted by its credit hours. An A (4.0) in a 4-credit class, a B (3.0) in a 3-credit class and a C (2.0) in a 3-credit class give (16 + 9 + 6) ÷ 10 = 3.1.

When you’d actually use a weighted average

  • Figuring out what you need on the final. Weight each part of your grade by the syllabus percentages, and see how much that last exam can move things before you decide how much coffee the week requires.
  • Your real average cost per share. Bought 10 shares at $50 and 30 more at $40? Weight each price by the number of shares: your average cost is $42.50, not $45.
  • Judging a restaurant fairly. A 4.8 rating from 12 reviews and a 4.2 from 900 reviews aren’t equal. Weighting by review count tells you which number to trust.

How we calculate

Each value is multiplied by its weight, the products are added, and the total is divided by the sum of the weights. Weights can’t be negative, and at least one weight must be above zero. Results are shown rounded to at most four decimal places, alongside the simple (unweighted) average for comparison. For plain lists of numbers, use the average calculator.

Frequently asked questions

What is a weighted average?

A weighted average is an average where some values count more than others. Each value is multiplied by its weight, the results are added, and the total is divided by the sum of the weights.

Do the weights have to add up to 100?

No. The formula divides by the total of the weights, so weights of 1, 2 and 3 work just as well as 20%, 30% and 50%.

How is a weighted average different from a regular average?

A regular average treats every value equally. A weighted average lets important values count more, so a final exam worth 50% moves the result more than a quiz worth 10%.

How do I calculate a weighted grade?

Enter each score as a value and its percentage of the course as the weight. For example, 92 (25%), 84 (25%) and 75 (50%) gives a weighted grade of 81.5.

Can I use percentages as weights?

Yes. Enter 30% as 30. The calculator divides by the total of the weights, so percentages that add up to 100 give the same result as decimals that add up to 1.

How do I calculate GPA with a weighted average?

Use each course's grade points as the value and its credit hours as the weight. An A (4.0) in a 4-credit class, a B (3.0) in a 3-credit class and a C (2.0) in a 3-credit class give a GPA of 31 ÷ 10 = 3.1.