Mean Calculator

The Mean Calculator computes all three classical Pythagorean means of a list of numbers in one place: the arithmetic mean, the geometric mean and the harmonic mean.

Paste your values separated by commas, spaces or new lines, and it instantly returns each average along with the count and the sum, so you can compare the three measures side by side.

Each mean answers a different question.

The arithmetic mean is the everyday average — add the values and divide by how many there are — and it is right for things that simply add up, like test scores or temperatures.

The geometric mean multiplies the values and takes the n-th root, which is the correct choice for growth rates, ratios and anything that compounds, such as investment returns over several years.

The harmonic mean is the reciprocal-based average and is the proper way to average rates like speeds or price-to-earnings ratios.

Because the geometric and harmonic means involve multiplication and reciprocals, they are only defined when every value is positive.

If your list contains a zero or a negative number, the tool clearly shows a dash for those two means while still giving you the arithmetic mean.

The calculation is numerically stable — the geometric mean is computed with logarithms to avoid overflow on long lists.

Everything runs locally in your browser, so your data is never uploaded or stored, and it works offline once the page has loaded.

Copy a one-line summary of all three means with a single click.