Excel TRUNC Function

Use the TRUNC function to remove the fractional part of a number and return just the integer. For example, TRUNC(4.9) will return 4, and TRUNC(-3.5) will return -3. TRUNC does not do any rounding, it simply returns the integer part of the number.

Example #1 - basic usage

=TRUNC(4.9) // returns 4
=TRUNC(-3.5) // returns -3

Example #2 - set number of decimal places

TRUNC can also be used to return a set number of decimal places without rounding, using the num_digits argument. For example, TRUNC (PI(), 2) will return 3.14 and TRUNC (PI(), 3) will return 3.141.

TRUNC (PI(), 2) // returns 3.14
TRUNC (PI(), 3) // returns 3.141

TRUNC vs INT

TRUNC is similar to the INT function because they both can return the integer part of a number. However, TRUNC simply truncates a number, while INT actually rounds a number down to an integer. With positive numbers, and when TRUNC is using the default of 0 for num_digits,  both functions return the same results. With negative numbers, the results can be different. INT(-3.1) returns -4, because INT rounds down to the lower integer. TRUNC(-3.1) returns -3. If you simply want the integer part of a number, you should use TRUNC.

Rounding functions in Excel

Excel provides a number of functions for rounding:

• To round normally, use the ROUND function.
• To round to the nearest multiple, use the MROUND function.
• To round down to the nearest specified place, use the ROUNDDOWN function.
• To round down to the nearest specified multiple, use the FLOOR function.
• To round up to the nearest specified place, use the ROUNDUP function.
• To round up to the nearest specified multiple, use the CEILING function.
• To round down and return an integer only, use the INT function.
• To truncate decimal places, use the TRUNC function.