Windows Calculator

Now that I made you do it by hand, what if I told your there was an easy way? All versions of Windows contain a handy calculator accessory.  A lot of people don't realize all that this calculator can do.  To get to the calculator in Windows 9.x or NT, click on the Start Button, Accessories and Calculator.  From the View menu of the calculator choose Scientific.

Note the option buttons Hex, Dec, Oct and Bin – these represent 4 different numbering systems.  To convert from one system to the other, simply click on the desired base’s option button. 

Let’s first try translating from Decimal to Binary.  Make sure that the Dec mode is selected, then type in the number, 1071950.  Now click on the Binary button. Do your results match mine?

Let’s try another. Make sure that the Bin button is selected.  Type in 10010011 and then press the Dec button. The result is 147. When doing calculations like this, don’t forget to first put the calculator into the mode you want to convert FROM, enter the number, and then click on the button of the mode you want to convert TO.  I’ve seen people forget to do this many times.

Let’s try one more. Make sure the Decimal input mode is selected. Enter the number 255 and change it to Binary. The result should be 11111111. Remember that the number 255 is the largest decimal number that you can make out of eight binary digits – it’s a big deal with nerds!

You can use this calculator to quiz yourself. Set the option button to binary and type in a string of ones and zeros. Figure it out on paper and then push the Dec button to reveal the calculator's answer.

For the A+ exam, you should know how to convert an eight-bit binary number into its decimal equivalent. If, in your career, you go on to work with and setup networks, you will also need to know how to do this.

Take some time and practice doing the conversion in your head or on paper and then using the calculator to find the answer.

Try these numbers (note that the calculator cuts off all leading zeros. 0010 simply becomes 10):

11011011
00110011
10000001
10011000
11111111
00001111
10000000

click here to see the answers.