Excel TRUNC Function

Related Functions:
ROUND
ROUNDDOWN
ROUNDUP

Basic Description

The Excel Trunc function truncates a supplied number to a specified number of decimal places.

The syntax of the function is:

TRUNC( number, [num_digits] )

Where the arguments are listed in the table below:

number-The number that is to be truncated.
[num_digits]-

An optional argument that specifies the number of decimal places to truncate the supplied number to.

If omitted, the [num_digits] argument uses the default value 0.

Note that:

  • A positive [num_digits] value specifies the number of digits to the right of the decimal point;
  • If [num_digits] is 0 (or is omitted), the supplied number is truncated to the nearest integer;
  • A negative [num_digits] value specifies the number of digits to the left of the decimal point.


Trunc Function Examples

Column B of the following spreadsheet shows several examples of the Excel Trunc function:

 Formulas:
 AB
199.999=TRUNC( A1, 1 )
299.999=TRUNC( A2, 2 )
399.999=TRUNC( A3 )
499.999=TRUNC( A4, -1 )
5-99.999=TRUNC( A5, 2 )
6-99.999=TRUNC( A6, -1 )
 Results:
 AB
199.99999.9
299.99999.99
399.99999
499.99990
5-99.999-99.99
6-99.999-90

The example in cell B3 of the above spreadsheet shows that, when the [num_digits] argument is omitted, it takes the default of 0. I.e. the supplied number is truncated to an integer.


Further information on the Excel Trunc Function is provided on the Microsoft Office website. If you require different rounding rules, check out our comparison of Excel Rounding Functions.