Average Calculator

The formula

The arithmetic mean is the sum of the values divided by how many there are:

Average = (x₁ + x₂ + … + xₙ) ÷ n

Type your numbers separated by commas, spaces or semicolons, with a point for decimals (12.5). If you prefer a decimal comma, separate the numbers with semicolons: 12,5; 14; 15,5.

Worked examples

• Test scores 12, 15, 18 and 20: sum 65, four values, average 16.25.
• Daily temperatures 12, 14, 15, 9 and 17 °C: sum 67 ÷ 5 = 13.4 °C.

Mean, median and mode

The average is one way of describing a "typical" value, but not always the best one:

• Median: the middle value once the list is sorted. For 9, 12, 14, 15, 17 it is 14.
• Mode: the most frequent value, useful for categories (most common shoe size).

The mean is sensitive to extreme values. Five monthly salaries of €2,000, €2,100, €2,200, €2,300 and €12,000 have a mean of €4,120, but a median of €2,200 — far more representative of what most people earn. That is why statistics offices often report median income rather than average income.

Weighted average

If some values count more than others — exam subjects with different coefficients, or products bought in different quantities — a simple average is wrong. Use the weighted average calculator, which multiplies each value by its weight before dividing by the total of the weights.

Tips

• Check for typing errors: one misplaced digit (150 instead of 15) can shift the mean a lot.
• The calculator also shows how many values it counted, which helps spot a missing or extra number.
• The average of percentages is only meaningful if each percentage refers to the same total.

Formulas and content last reviewed: October 2026 · About