Free Trimmed Mean Calculator

Compute a trimmed mean by removing extreme values before averaging to reduce outlier influence.

Trimmed Mean (drop highest & lowest)

12.0000

Regular Mean27.2000
Difference15.2000

Trimmed Mean (drop highest & lowest) vs Smallest Value

How the Trimmed Mean Works

Approach

1. Sort the values from smallest to largest 2. Remove a fixed percentage from each end (here, one value from each end) 3. Average the remaining values

Trimmed Mean = Sum of remaining values / Count of remaining values

This technique protects the average from outliers while still using most of the data. A common choice is a 20% trimmed mean, which removes the top and bottom 20% of observations.

Example Calculation

Data: 2, 10, 12, 14, 98. Compute the trimmed mean removing one value from each end.

  1. 01Sorted values: 2, 10, 12, 14, 98
  2. 02Remove lowest (2) and highest (98)
  3. 03Remaining: 10, 12, 14
  4. 04Trimmed Mean = (10 + 12 + 14) / 3 = 12
  5. 05Compare: Regular Mean = 136 / 5 = 27.2 (heavily influenced by 98)

Frequently Asked Questions

Learn More

Understanding the Normal Distribution

Learn what the normal distribution is, why it matters in statistics, and how to use the bell curve for probability calculations, z-scores, and real-world data analysis.

Related Calculators