microsoft office excel

Think Microsoft’s Excel can do math? Think again. AppScout pointed out that Excel 2007 can’t multiply certain numbers and you can try it for yourself! For those who rely on Excel for their jobs to calculate large numbers, this is a rather serious problem. It was initially exposed on the Microsoft Public Excel Group where one of their members reported this major bug to Microsoft, although Microsoft has yet to respond.

To try it for yourself, open up Excel 2007 and multiply 850 by 77.1. If you’re unfamiliar with performing calculations in Excel, you’d enter the following into a cell:


Once you do that, you’ll discover the answer according to Excel 2007 is 100,000. But now get out a calculator or a piece of paper and pencil and do the same calculation and you’ll find that the answer is really 65,535. That’s not the only number Excel has problems with either. According to Neil Rubenking over at App Scout, he found  ten thousand of these multiplication calculations that gave the wrong answer! He also gave some insight as to the reason this might be happening:

We won’t know just why the problem comes up until Microsoft speaks out, but there is one thing about 65535 – it’s the very largest 16-bit number. In binary it’s a string of 16 ones. In hexadecimal (the programmer’s friend) it’s FFFF. But converting the “problem” results to hexadecimal in Excel yields FFFE. That’s surely a clue.

This is almost just as bad as Excel being unable to add 1 + 1! Even with all the current Excel patches installed, the problem still exists. Hopefully Microsoft speaks up soon and resolves this serious Excel multiplication bug.