27 November 2008

C# Convert Hexadecimal to Binary String Conversion

There is no need to code tons of codes, loops, to convert hex to binary string. Convert.ToInt32 function is very useful for this purpose.
Let's convert the "A" character to binary format.
private string hex2binary(string hexvalue)
string binaryval = "";
binaryval = Convert.ToString(Convert.ToInt32(hexvalue, 16), 2);
return binaryval;
When we call hex2binary("A"); it will return "1010" similar samples below;

hex2binary("1a"); will return "11010";
hex2bianry("1a2c"); will return "1101000101100"; and so on.

Keep in mind that this hex to binary conversion style uses 32 bit integer number.


Anonymous said...

Thanks alot!!

Anonymous said...

Tahnk you.

Anonymous said...

very very thank you

Anonymous said...


후니 said...

Thank you very much!~

parul said...

Thanks a lot!!!!!!!!!! :)

parul said...

Hi I am not able to convert a very large hexa value in binary using the code u provided???? for eg

ck said...

string binaryval = string.Empty;

strInput = "F23E44810EE1805A0000004004000062";

foreach (char ch in strInput)
binaryval += Convert.ToString(Convert.ToInt32(ch.ToString(), 16), 2);

Matias said...

For large numbers you must use Convert.ToInt64.
strBinValue = Convert.ToString(Convert.ToInt64(strHex, 16), 2);

Anonymous said...

Thank you!!!!!!!!!!!!!

Stonkie said...

@ck I didn't try, but I think you'll lose zeros when parsing characters that translate to less than 4 bits. You should add them by padding each value with zeros up to 4 bits.

Leonardo Reis said...

Thank You!!!

Anonymous said...

hi, I agree Stonkie zeros lose if first bit is zero of 4 bits' .how can I fix this problem.

Jared said...

you can just do it all as one line, like this

public static string hex2binary(string hexvalue)
return Convert.ToString(Convert.ToInt32(hexvalue, 16), 2);

Anonymous said...

Is this valid to Convert the hexadecimal to 4 bit binary too??

ShaneG said...

Thanks, I forget this every time. Should probably write it down somewhere handy....

Anonymous said...


Anonymous said...

I'll have to implement this into my code tonight when I get back to my place, should do what I want hopefully. (Let's say I have a file that was way to large LOL)

SandeepV said...

just a modification to the above code, as suggested by stonkie:

string binaryval = "";
binaryval = Convert.ToString(Convert.ToInt32(hexString, 16), 2);
if (binaryval.Length != hexString.Length * 4)
int bitsdifference = hexString.Length * 4 - binaryval.Length;
for (int i = 0; i < bitsdifference; i++)
binaryval = "0" + binaryval;
return binaryval;

Stonkie said...

const String strInput = "F23E44810EE1805A0000004004000062";

String result = strInput
.Aggregate(new StringBuilder(), (builder, c) =>
builder.Append(Convert.ToString(Convert.ToInt32(c.ToString(), 16), 2).PadLeft(4, '0')))


It basically does the same as SandeepV's code but it uses PadLeft to save a loop, a StringBuilder for performance on long input strings and LINQ because I can.

John Ortiz Ordoñez said...

Thanks for sharing!

It is working for my application that I am creating!