HesapHanem

Mean Absolute Deviation Calculator

Find the mean absolute deviation.

How it is calculated

The list is split on spaces and commas, and any entry that is not a number is silently skipped. With n valid values, the tool computes the mean and then the average absolute distance from it: MAD = Σ|xi − x̄| ÷ n, where x̄ = Σxi ÷ n. The divisor is n for the whole list you give, so it treats the numbers as the complete dataset. Both the mean and MAD are shown to two decimals, in the same unit as your data. This is the deviation around the mean, not around the median.

Worked example

Data: 2, 4, 4, 4, 5, 5, 7, 9. The sum is 40 and n = 8, so the mean is 5.00. Distances from 5 are 3, 1, 1, 1, 0, 0, 2 and 4, which add up to 12. Then 12 ÷ 8 = 1.50. The mean absolute deviation is 1.50 around a mean of 5.00.

Try this example →

Common mistakes

  • Confusing MAD with standard deviation. MAD averages plain distances while standard deviation squares them first, so the two numbers differ (here 1.50 versus 2.00 for the same data).
  • Assuming a typo is flagged. A word or a number with a stray character is dropped without a warning, so n and the mean may be based on fewer values than you pasted.
  • Using a decimal comma in the list, such as 2,5, which is read as two separate numbers 2 and 5.
  • Mistaking it for deviation around the median. Some textbooks define MAD that way; this tool always measures from the mean.

About this calculator

This calculator finds the mean absolute deviation (MAD) of a dataset — the average distance of each value from the mean, ignoring the sign of the difference. It's calculated by taking the mean, subtracting it from every value, taking the absolute value of each difference, and averaging those.

Statistics students use it as a simpler alternative to standard deviation for measuring how spread out a dataset is, and analysts use it to gauge forecast accuracy or data consistency without the squaring that lets a single outlier dominate the picture.

Was this helpful?

You can pick up to 3 reactions.

Comments (1)

  • Editorial team

    Deviations are measured from the mean, not the median, and divided by the number of values. Anything in the list that is not a valid number is skipped without a warning, so a typo such as a letter O for a zero would shrink your data set unnoticed; count the entries. As a sanity check, the standard deviation of the same data is never smaller than this result. Do you use mean absolute deviation or standard deviation in your field?

Popular calculators

Loan Calculator

Monthly payment, total interest and full amortization schedule.

Percentage Calculator

Percent change, percent of, and ratio calculations.

Discount Calculator

Calculate final price, savings, and discount amount.

BMI Calculator

Body mass index from height and weight (metric or imperial).

Age Calculator

Compute your exact age in years, months and days from a birth date.

Compound Interest Calculator

Calculate the final amount and interest earned with compounding.

All Calculators