Using the TRUNC Worksheet Function

There may be times when you need to "truncate" a number at a certain number of digits. For this purpose Excel provides the TRUNC worksheet function. TRUNC can work with either one or two arguments, as necessary for your purposes. When use with only a single argument, TRUNC simply drops off any part of the number after the decimal point. For instance, consider the following:

=TRUNC(12.34)

This returns a value of 12, which is everything to the left of the decimal point. This result may look familiar, and you may be tempted to think that TRUNC does the same thing as the INT function. There are several differences, however. Consider a scenario where the argument is less than zero:

=TRUNC(-43.21)

In this instance, TRUNC returns –43, not –44 as INT would. Remember, when using TRUNC with a single argument, it simply drops everything to the right of the decimal point.

If you use a second argument with TRUNC, you can specify the number of decimal places at which you want the truncation to occur. For instance, the following formula returns a value of 12.3:

=TRUNC(12.34,1)

If you use a negative value for the second argument, the truncation takes place to the left of the decimal point. This has the same effect as returning powers of 10. For instance, consider the following example, which returns the value of 1200:

=TRUNC(1234.5678,-2)