Mean Calculator

Mean Calculator - Calculate Arithmetic Mean

Calculate the arithmetic mean (average) of any dataset with our free online mean calculator. Simply enter your numbers separated by commas, spaces, or new lines and get instant results including the mean, sum, and count.

What is the Mean?

The mean, also known as the arithmetic mean or average, is a measure of central tendency that represents the typical value in a dataset. It is calculated by summing all values and dividing by the number of values.

Mean Formula

Mean = (Sum of all values) / (Number of values)

Example Calculation

Find the mean of: 5, 8, 12, 15, 20

Step 1: Sum = 5 + 8 + 12 + 15 + 20 = 60
Step 2: Count = 5
Step 3: Mean = 60 / 5 = 12

Result: The mean is 12

How to Use This Calculator

1. Enter Your Numbers - Input numbers separated by commas, spaces, or new lines
2. Choose Precision - Select the number of decimal places for your result
3. Click Calculate - Get instant results with mean, sum, and count

When to Use the Mean

The mean is best used when:

• Data is symmetrical - Normally distributed without significant skew
• No extreme outliers - Outliers can significantly distort the mean
• Interval/ratio data - Continuous numerical data
• Mathematical operations needed - Mean is required for further statistical calculations

Mean vs. Median vs. Mode

Mean: Sum divided by count - sensitive to outliers

Median: Middle value when sorted - resistant to outliers

Mode: Most frequent value - best for categorical data

Example with Outlier:

Data: 5, 8, 12, 15, 100

• Mean: 28 (skewed by outlier)
• Median: 12 (not affected)

Types of Means

Arithmetic Mean

The standard mean calculated by summing values and dividing by count. This is what most people mean by "average."

Weighted Mean

Some values count more than others:

Weighted Mean = Σ(Value × Weight) / ΣWeights

Geometric Mean

Used for growth rates and ratios:

Geometric Mean = nth root of (product of all values)

Harmonic Mean

Used for rates and speeds:

Harmonic Mean = n / Σ(1/value)

Practice Problems

Problem 1

Find the mean of: 10, 15, 20, 25, 30

Solution: Sum = 100, Count = 5, Mean = 20

Problem 2

A student scored 85, 92, 78, 88, and 95 on tests. What's the mean score?

Solution: Sum = 438, Count = 5, Mean = 87.6

Problem 3

Daily sales: $120, $150, $180, $200, $175. Find the mean daily sales.

Solution: Sum = $825, Count = 5, Mean = $165