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iwaddo's avatar
iwaddo
Copper Contributor
Apr 01, 2026

Excel says two numbers are not equal

Column A are numbers typed into the cells.

Column B, the numbers in B1 to B3 are also typed in.

Cell B4 is SUM(b1:b3)

C4 is =B4=A4

 

Can someone please explain why excel is saying the two numbers in A4 & B4 are not equal.

I understand about using rounding or truncation with large calculations but I've never seen anything like this on such a simple calculation.

I've tried this on a new spreadsheet and the results are the same.

I am using Excel Version 16.109 (26033013) on a Mac.

Thank you for your help. 

excel
Excel on Mac

1 Reply

  • m_tarler's avatar
    m_tarler
    Bronze Contributor
    Apr 01, 2026

    There are much better detailed descriptions of this but basically excel needs to use binary to represent those numbers.  Binary can represent whole numbers very easily but even then very large numbers reach a limit.  For fractions it is even more so.  So simply increase the number of digits being displayed and you will see:

    so excel has to represent 6827.81 using binary and then -6613.99 using binary and add those 2 numbers together and those 2 representations happen to have just enough round off error to creep into a very low digit that is within the significance kept by excel.  If you break those numbers up to be 6827 + 0.81 it doesn't happen or -6613 - 0.99 it doesn't happen.  There are many of these rare occasions where that last bit rounds (or flips) up.  If you are really interested in the details I welcome you to dive deeper into Excel round off errors but just make sure to use ROUND(..) when checking for exact values or >= or <= when comparing values.