How to Truncate Decimals in Excel with TRUNC

TRUNC chops off decimals without rounding — and, unlike INT, treats negative numbers the way people expect.

You will learn to

• Cut a number to one decimal place
• See why TRUNC and INT differ on negatives
• Count values where the two disagree

How it works

TRUNC(number, [num_digits]) simply cuts a number off after the digits you keep: =TRUNC(-18.76,1) returns -18.7 and =TRUNC(4.58) returns 4. Nothing is rounded up or down — the extra digits are just dropped.

For positive numbers TRUNC and INT give the same whole number. For negative numbers they differ: INT rounds down (=INT(-0.45) is -1) while TRUNC moves toward zero (=TRUNC(-0.45) is 0). Use TRUNC whenever you mean “drop the decimals”.

=TRUNC(B2,1)