By ToolzHive
About this tool
Mean, standard deviation, standard error, median, quartiles and CI from raw data.
How to use Mean, SD & SEM Calculator
- Paste your values from a spreadsheet column, or type them separated by commas or spaces.
- Choose the confidence level for the interval of the mean.
- Copy the statistics, or the ready-made reporting sentence.
Worked example
Ten readings averaging 13.53 with SD 1.10 have an SEM of 0.35 and a 95% confidence interval of 12.74 to 14.32.
What is the difference between SD and SEM?
SD describes how spread out the data are. SEM describes how precisely the mean is estimated, and it shrinks as the sample grows.
Which should I report?
Report SD to describe your sample and a confidence interval to show the precision of the mean. Avoid using SEM just because it looks smaller.
Put this guide into practice
- Mean, SD & SEM Calculator — Mean, standard deviation, standard error, median, quartiles and CI from raw data.