Python conversion from binary string to hexadecimal

Question

How can I perform a conversion of a binary string to the corresponding hex value in Python?

I have 0000 0100 1000 1101 and I want to get 048D I'm using Python 2.6.

score 95 · Answer 1 · edited Aug 18 '18 at 14:04

95

int given base 2 and then hex:

>>> int('010110', 2)
22
>>> hex(int('010110', 2))
'0x16'
>>> 

>>> hex(int('0000010010001101', 2))
'0x48d'

The doc of int:

int(x[, base]) -> integer

Convert a string or number to an integer, if possible.  A floating
point argument will be truncated towards zero (this does not include a string representation of a floating point number!) When converting a string, use the optional base. It is an error to supply a base when converting a non-string. If base is zero, the proper base is guessed based on the string content. If the argument is outside the integer range a long object will be returned instead.

The doc of hex:

hex(number) -> string

Return the hexadecimal representation of an integer or long

integer.

edited Aug 18 '18 at 14:04

ivan_pozdeev

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answered Jan 15 '10 at 14:51

Eli Bendersky

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14

This fails to preserve leading 0s. – Ignacio Vazquez-Abrams Jan 15 '10 at 14:58
2

@Ignacio, you're right, but I don't think the OP asked about that. In any case, ++ to your answer for pointing that out. – Eli Bendersky Jan 15 '10 at 16:14
4

@Eli: the OP specifically said he wanted `048d` i.e. wants leading zero, DOESN'T want 0x – John Machin Jan 15 '10 at 20:44
1

This may not preserve the leading zeroes, but it's much more readable than the clever hacks below. – Dennis Oct 30 '13 at 17:30

Ignacio Vazquez-Abrams · Answer 2 · 2010-01-15T15:58:44.973

35

bstr = '0000 0100 1000 1101'.replace(' ', '')
hstr = '%0*X' % ((len(bstr) + 3) // 4, int(bstr, 2))

edited Jan 15 '10 at 15:58

answered Jan 15 '10 at 14:53

Ignacio Vazquez-Abrams

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@SO should really add per-language coloring. Here it thinks // is a C++ comment and grays out everything following. // in Python isn't a comment, but truncating integer division – Eli Bendersky Jan 15 '10 at 16:16
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Brilliant answer. I am surprised why it's not upvoted/accepted yet. – Andrei Jul 23 '13 at 09:03
2

@Dennis the first line is just cleaning up the binary string. The second line formats it as a hexadecimal string, padded to `(len(bstr) + 3) // 4` hex digits, which is `number of bits / 4` rounded up, i.e. the number of hex digits required. The last part of the second line parses the binary string to a number, because the %X format specifier is for numbers not binary strings. – user253751 Mar 27 '14 at 07:41
What is the equivalent in Python 3? Using "".format() – Djunzu Nov 01 '17 at 22:02

score 27 · Answer 3 · answered Nov 09 '15 at 21:16

27

Use python's binascii module

import binascii

binFile = open('somebinaryfile.exe','rb')
binaryData = binFile.read(8)

print binascii.hexlify(binaryData)

answered Nov 09 '15 at 21:16

user3394040

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score 7 · Answer 4 · edited Aug 10 '12 at 06:13

7

Converting Binary into hex without ignoring leading zeros:

You could use the format() built-in function like this:

"{0:0>4X}".format(int("0000010010001101", 2))

edited Aug 10 '12 at 06:13

Community

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answered Jan 15 '10 at 15:44

Gareth Williams

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This works only for 2-byte numbers, while Ignacio's answer works for any length. – Andrei Jul 23 '13 at 08:53
You still need to replace spaces if any. – Andrei Jul 23 '13 at 09:01

score 4 · Answer 5 · edited Mar 12 '22 at 07:50

4

Using no messy concatenations and padding :

'{:0{width}x}'.format(int(temp,2), width=4)

Will give a hex representation with padding preserved

edited Mar 12 '22 at 07:50

Darien

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answered Jul 30 '13 at 11:27

Sam Palmer

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babis21 · Answer 6 · 2018-08-08T10:32:32.517

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On python3 using the hexlify function:

import binascii
def bin2hex(str1):
    bytes_str = bytes(str1, 'utf-8')
    return binascii.hexlify(bytes_str)

a="abc123"
c=bin2hex(a)
c

Will give you back:

b'616263313233'

and you can get the string of it like:

c.decode('utf-8')

gives:

'616263313233'

edited Aug 08 '18 at 10:32

answered Aug 08 '18 at 10:24

babis21

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Tomas · Answer 7 · 2021-10-01T11:22:40.023

3

I would do:

dec_str = format(int('0000010010001101', 2),'x')
dec_str.rjust(4,'0')

Result: '048d'

edited Oct 01 '21 at 11:22

answered Oct 22 '19 at 15:19

Tomas

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neotam · Answer 8 · 2020-04-21T11:28:37.300

To convert binary string to hexadecimal string, we don't need any external libraries. Use formatted string literals (known as f-strings). This feature was added in python 3.6 (PEP 498)

>>> bs = '0000010010001101'
>>> hexs = f'{int(bs, 2):X}'
>>> print(hexs)
>>> '48D'

If you want hexadecimal strings in small-case, use small "x" as follows

f'{int(bs, 2):x}'

Where bs inside f-string is a variable which contains binary strings assigned prior

f-strings are lost more useful and effective. They are not being used at their full potential.

score 0 · Answer 9 · answered Jul 14 '13 at 09:15

0

format(int(bits, 2), '0' + str(len(bits) / 4) + 'x')

answered Jul 14 '13 at 09:15

Dmitry Sobolev

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You need to replace spaces before conversion. – Andrei Jul 23 '13 at 08:57

Tor Valamo · Answer 10 · 2010-01-15T15:12:59.897

0

Assuming they are grouped by 4 and separated by whitespace. This preserves the leading 0.

b = '0000 0100 1000 1101'
h = ''.join(hex(int(a, 2))[2:] for a in b.split())

edited Jan 15 '10 at 15:12

answered Jan 15 '10 at 14:52

Tor Valamo

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you don't need list comprehension there – SilentGhost Jan 15 '10 at 15:00

score 0 · Answer 11 · answered Apr 03 '15 at 15:44

For whatever reason I have had issues with some of these answers, I've went and written a couple helper functions for myself, so if you have problems like I did, give these a try.

def bin_string_to_bin_value(input):
   highest_order = len(input) - 1
   result = 0
   for bit in input:
      result = result + int(bit) * pow(2,highest_order)
      highest_order = highest_order - 1
   return bin(result)

def hex_string_to_bin_string(input):
   lookup = {"0" : "0000", "1" : "0001", "2" : "0010", "3" : "0011", "4" : "0100", "5" : "0101", "6" : "0110", "7" : "0111", "8" : "1000", "9" : "1001", "A" : "1010", "B" : "1011", "C" : "1100", "D" : "1101", "E" : "1110", "F" : "1111"}
   result = ""
   for byte in input:
      result =  result + lookup[byte]
   return result
def hex_string_to_hex_value(input):
   bin_string = hex_string_to_bin_string(input)
   bin_value = bin_string_to_bin_value(bin_string)
   return hex(int(bin_value, 2))

They seem to work well.

print hex_string_to_hex_value("FF")
print hex_string_to_hex_value("01234567")
print bin_string_to_bin_value("11010001101011")

results in:

0xff
0x1234567
0b11010001101011

Where is bin_value_to_hex_string? – Léo Léopold Hertz 준영 Jul 10 '15 at 09:56 — Léo Léopold Hertz 준영, Jul 10 '15 at 09:56

score -2 · Answer 12 · answered Jan 15 '10 at 15:42

-2

>>> import string
>>> s="0000 0100 1000 1101"
>>> ''.join([ "%x"%string.atoi(bin,2) for bin in s.split() ]  )
'048d'
>>>

or

>>> s="0000 0100 1000 1101"
>>> hex(string.atoi(s.replace(" ",""),2))
'0x48d'

answered Jan 15 '10 at 15:42

ghostdog74

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so what's the problem? Its still in Python 2.6 – ghostdog74 Jan 15 '10 at 23:51
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It's still in 2.X for the benefit of people who were using it in 1.X. string.atoi() is according to the 2.6 docs """Deprecated since version 2.0: Use the int() built-in function.""" and is not present in 3.X. The 2.X implementation of string.atoi() calls int(). There is no good reason for telling some newcomer that string.atoi() even exists let alone telling them to use it instead of telling them to use int(). – John Machin Jan 16 '10 at 09:08

score -3 · Answer 13 · answered Aug 29 '18 at 09:50

 x = int(input("press 1 for dec to oct,bin,hex \n press 2 for bin to dec,hex,oct \n press 3 for oct to bin,hex,dec \n press 4 for hex to bin,dec,oct \n"))


   if x is 1:

  decimal =int(input('Enter the decimal number: '))

  print(bin(decimal),"in binary.")
 print(oct(decimal),"in octal.")
    print(hex(decimal),"in hexadecimal.")

      if x is 2:

       binary = input("Enter number in Binary Format: ");

  decimal = int(binary, 2);
  print(binary,"in Decimal =",decimal);
  print(binary,"in Hexadecimal =",hex(decimal));
  print(binary,"in octal =",oct(decimal));

    if x is 3:

      octal = input("Enter number in Octal Format: ");

      decimal = int(octal, 8);
      print(octal,"in Decimal =",decimal);
      print(octal,"in Hexadecimal =",hex(decimal));
      print(octal,"in Binary =",bin(decimal));

          if x is 4:

         hex = input("Enter number in hexa-decimal Format: ");

      decimal = int(hex, 16);
        print(hex,"in Decimal =",decimal);
      print(hex,"in octal =",oct(decimal));
        print(hex,"in Binary =",bin(decimal));

Python conversion from binary string to hexadecimal

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