TRUNC vs ROUNDDOWN

[amiroo]

hi,
does anybody knows what is difference between TRUNC and ROUNDDOWN functions in excel?

except optional or required for second argument

 

[RoryA]

As far as I know, there is no other difference.

 

[nanndu141]

both are the same.

 

[amiroo]

As far as I know, there is no other difference.

thank you Rory
so why Microsoft released two function with similar output?

 

[RoryA]

Ask them.

 

[Peter_SSs]

My guess is that ROUNDDOWN fits with the whole range of rounding functions and TRUNC may have been originally included to provide compatibility with earlier spreadsheet forms that perhaps had such a function.

 

[joeu2004]

If we want to truncate (toward zero) to an integer, we must write ROUNDDOWN(A1,0), whereas we can write TRUNC(A1).

In other words, the second parameter is optional for TRUNC; not for ROUNDDOWN.

But I agree with Peter: the most likely explanation is compatibility with either other spreadsheets or customer expectations.

BTW, note the difference between TRUNC(A1) and INT(A1) when A1 is negative. The latter rounds down away from zero; that is, always to the left of the real number line.