Weighted Average Calculator

Last Updated on March 2, 2026 | 2 : 30 pm by Anas Brittany

Use this weighted average calculator to find the weighted mean of a set of values. Enter each value along with its weight (importance or percentage) to calculate the overall weighted average instantly.

What Is a Weighted Average?

A weighted average is an average where some values contribute more than others. Each value is multiplied by a weight that represents its importance.

Unlike a simple average, where all numbers are treated equally, a weighted average reflects the relative significance of each value.

Weighted Average Formula

The formula for weighted average is:

Weighted Average = Σ(value × weight) ÷ Σ(weights)

Where:

• Value = the data point
• Weight = the importance or percentage
• Σ = sum of all values

Example Calculation

Scores and weights:

• 80 (weight 20)
• 90 (weight 30)
• 70 (weight 50)

Weighted sum:
(80×20) + (90×30) + (70×50) = 1600 + 2700 + 3500 = 7800

Total weight:
20 + 30 + 50 = 100

Weighted average:
7800 ÷ 100 = 78

Common Uses of Weighted Average

Weighted averages are used in:

• School grade calculations
• GPA and academic scoring
• Financial portfolio returns
• Business performance metrics
• Statistics and data analysis

Percentages vs Weights

Weights can be:

• Percentages (must total 100)
• Points or units (any total works)

The formula automatically adjusts based on the total weight.

Frequently Asked Questions

What is the difference between average and weighted average?

A simple average treats all values equally. A weighted average gives more influence to certain values.

Do weights have to add up to 100?

No. The calculator divides by the total weight, so any total works.

Can weights be decimals?

Yes. Weights can be whole numbers, percentages, or decimals.