Enter your data in cells (e.g., A1:A10).
Use the sample standard deviation: `=STDEV.S(A1:A10)`
Use the population standard deviation: `=STDEV.P(A1:A10)`
For a range with blanks ignored: `=STDEV.S(IF(A1:A10<>“”,A1:A10))` (array formula; confirm with Ctrl+Shift+Enter if required)
For a named range (e.g., `Data`): `=STDEV.S(Data)` or `=STDEV.P(Data)`
If you have a normal distribution and need a standard deviation from variance: `=SQRT(variance_cell)`