Got a version of Excel that uses the menu interface (Excel 97, Excel 2000, Excel 2002, or Excel 2003)? This site is for you! If you use a later version of Excel, visit our ExcelTips site focusing on the ribbon interface.
With more than 50 non-fiction books and numerous magazine articles to his credit, Allen Wyatt is an internationally recognized author. He is president of Sharon Parq Associates, a computer and publishing services company.
Learn more about Allen...
Please Note: This article is written for users of the following Microsoft Excel versions: 97, 2000, 2002, and 2003. If you are using a later version (Excel 2007 or later), this tip may not work for you. For a version of this tip written specifically for later versions of Excel, click here: Converting to Octal.
There are four types of numbering systems commonly used in programming: binary, octal, decimal, and hexadecimal. Each is simply a different method of expressing the exact same values. Excel makes it easy to convert between decimal and octal numbers, and provides two worksheet functions for that very purpose.
The first function is the DEC2OCT function. Suppose you have a decimal value in cell B7, and you want to know how to express that value in octal. In a different cell you could use the following formula:
If the value in B7 was 456, the result of the above formula would be 710. An interesting fact (and potential "gottcha") is that when the conversion is completed, Excel considers the result to be a number. Thus, if you added 8 to the resulting value above (710), Excel would return 718—a value impossible in octal. This simply means that Excel doesn't keep track of the numbering system used in a particular cell; it expects you to do that.
If you want to convert numbers back the other way, from octal to decimal, you can use the OCT2DEC worksheet function:
If you try to use this function with a value that is clearly not octal (such as 718), then Excel returns a #NUM! error value.
ExcelTips is your source for cost-effective Microsoft Excel training. This tip (2316) applies to Microsoft Excel 97, 2000, 2002, and 2003. You can find a version of this tip for the ribbon interface of Excel (Excel 2007 and later) here: Converting to Octal.
Solve Real Business Problems Master business modeling and analysis techniques with Excel and transform data into bottom-line results. This hands-on, scenario-focused guide shows you how to use the latest Excel tools to integrate data from multiple tables. Check out Microsoft Excel 2013 Data Analysis and Business Modeling today!