How to Convert from Decimal to Binary. By using Excel 2003, the decimal number can be converted into binary (decimal to binary). However, the function to convert decimal numbers to binary has the some limitations of which can be seen in the syntax and description below:

Syntax :
DEC2BIN(number,places)
Number is the decimal integer you want to convert. If number is negative, places is ignored and DEC2BIN returns a 10-character (10-bit) binary number in which the most significant bit is the sign bit. The remaining 9 bits are magnitude bits. Negative numbers are represented using two's-complement notation.
Places is the number of characters to use. If places is omitted, DEC2BIN uses the minimum number of characters necessary. Places is useful for padding the return value with leading 0s (zeros).
Remarks
If number < -512 or if number > 511, DEC2BIN returns the #NUM! error value.
If number is nonnumeric, DEC2BIN returns the #VALUE! error value.
If DEC2BIN requires more than places characters, it returns the #NUM! error value.
If places is not an integer, it is truncated.
If places is nonnumeric, DEC2BIN returns the #VALUE! error value.
If places is negative, DEC2BIN returns the #NUM! error value.

We tried to apply the function DEC2BIN,
Create a table like below



Then
in cell B3 enter the formula
= DEC2BIN (A3)
in cell C3 enter the formula
= DEC2BIN (A3, 4)
in cell D3 enter the formula
= DEC2BIN (A3, 8)

The result will look like below