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TRIMMEAN
TRIMMEAN removes a given proportion of outlier values from both tails of a dataset before computing the average, making it more robust than a plain AVERAGE when your data contains anomalies. Use it for survey scores, performance ratings, or any numeric series where extreme values would skew results.
Excel
=TRIMMEAN(A2:A5,0.2)Google Sheets
=TRIMMEAN(A2:A5,0.2)Try it with your data
Edit the grid or formula, then run it through a real spreadsheet engine — no signup.
Sample data — click any cell to edit
Runs server-side · free · no signup
How it works
- 1Select the numeric range that may contain outliers.
- 2Determine the trim percentage — for example, 0.2 drops the top 10% and bottom 10% of values.
- 3Enter =TRIMMEAN(range, percent) to get the mean of the remaining central data.
Need a version for your data?
Try: “Calculate the average customer score while ignoring the top and bottom 10% of extreme ratings”