| CALL | The results from a procedure in a DLL or code resource. |
| CEILING | The number rounded up to the nearest integer / significant figure. |
| CELL | The number or text string indicating information about a cell. |
| CHAR | The character with the corresponding ANSI number. |
| CHIDIST | The one tailed probability of the chi-squared distribution. |
| CHIINV | The inverse of the one tailed probability (function above). |
| CHITEST | The value from the chi-squared distribution. |
| CHOOSE | The value from a list of values, based on an index number. |
| CLEAN | The text string with all the non-printable characters removed. |
| CODE | The ANSI number for the first character in a text string. |
| COLUMN | The column number of the cell reference. |
| COLUMNS | The number of columns in a cell range or reference. |
| COMBIN | The number of combinations for a given number of items. |
| COMPLEX* | The complex number given real and imaginary coefficients. |
| CONCATENATE | The text string that is a concatenation of several strings. |
| CONFIDENCE | The confidence interval for a population mean. |
| CONVERT* | The number in one measurement system converted to another. |
| CORREL | The correlation coefficient between two data sets. |
| COS | The cosine of an angle in radians. |
| COSH | The hyperbolic cosine of a number. |
| COUNT | The number of numeric values in a list or array of numbers. |
| COUNTA | The number of non blank cells in a list or cell range. |
| COUNTBLANK | The number of blank cells in a list or cell range. |
| COUNTIF | The number of non blank cells that satisfies a condition. |
| COUPDAYBS* | The number of days between a coupon starting and settlement. |
| COUPDAYS* | The number of days between the next coupon and settlement. |
| COUPDAYSNC* | The number of days from the settlement date to the next coupon. |
| COUPNCD* | The next coupon date after the settlement date. |
| COUPNUM* | The number of coupons between the settlement and maturity. |
| COUPPCD* | The previous coupon date before the settlement. |
| COVAR | The average of the products of deviations for each data point pair. |
| CRITBINOM | The number where the binomial distribution is greater than a criterion value. |
| CUMIPMT* | The cumulative interest paid between two periods. |
| CUMPRINC* | The cumulative principal paid on a loan between two dates. |
