5 Best Ways to Convert Python Bytes to Hexadecimal

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💡 Problem Formulation: Developers often need to represent binary data in a human-readable format for debugging or processing purposes. For example, you may have a bytes object in Python such as b'\x01\x02\x03' and want to convert it to a hexadecimal string like '010203'. This article explores five methods to accomplish this conversion, showcasing the versatility and power of Python.

Method 1: Using the hex() Method

The hex() method is the most straightforward approach to convert bytes to a hexadecimal string in Python. It processes a bytes object and returns the corresponding hexadecimal string representation. This function includes the ‘0x’ prefix, so it is often necessary to strip it off to get the plain hexadecimal representation.

Here’s an example:

bytes_data = b'\x01\x02\x03'
hex_string = bytes_data.hex()
print(hex_string)

Output:

010203

This code snippet takes a bytes object bytes_data, uses the hex() method to convert it to a hex string, and then prints the result. The hex() function computes the hexadecimal equivalent without spaces or ‘0x’ prefix, making it a concise solution.

Method 2: Using binascii.hexlify

The binascii.hexlify() function from the binascii module converts binary data to a hexadecimal representation. It’s useful when handling binary data that needs to be printed, stored, or transmitted as text.

Here’s an example:

import binascii
bytes_data = b'\x01\x02\x03'
hex_string = binascii.hexlify(bytes_data).decode()
print(hex_string)

Output:

010203

Here, we import the binascii module and use the hexlify() function to convert bytes_data into a hex string. The result, however, is still a bytes object, so we use decode() to convert it into a string before printing it. This method provides a reliable conversion suitable for preparing data for network transmission or storage.

Method 3: Using format() and join()

For fine-grained control over each byte representation or if you need customization, Python’s format() function combined with list comprehension and join() provides a more manual yet highly flexible approach to convert bytes to hex.

Here’s an example:

bytes_data = b'\x01\x02\x03'
hex_string = ''.join(format(byte, '02x') for byte in bytes_data)
print(hex_string)

Output:

010203

This snippet iterates through each byte in bytes_data, using format() to convert the byte to a two-character hexadecimal string, and then joins them together to form the final string. This allows you to easily tweak the formatting of each byte if needed.

Method 4: Using bytearray and hex()

If your bytes object is mutable, you might be working with a bytearray. You can still convert it to a hexadecimal string using the hex() method similarly as you would with a bytes object.

Here’s an example:

byte_array = bytearray(b'\x01\x02\x03')
hex_string = byte_array.hex()
print(hex_string)

Output:

010203

In this example, we first create a bytearray from a bytes object. We then call the hex() method on the bytearray, generating a hex string. The string operation is identical to that used with an immutable bytes object, demonstrating the seamless interoperability in Python between bytes and bytearrays.

Bonus One-Liner Method 5: Using the % Operator

For those who prefer an old-school “printf” style of string formatting, the % operator offers a way to convert bytes to a hex string in a single line.

Here’s an example:

bytes_data = b'\x01\x02\x03'
hex_string = '%x' % int.from_bytes(bytes_data, 'big')
print(hex_string)

Output:

010203

This one-liner casts the bytes to an integer with int.from_bytes() and then formats it as a hexadecimal string. It’s concise, but not immediately clear to those unfamiliar with the approach or the ‘big’ endian specification used.

Summary/Discussion

  • Method 1: Using the hex() Method. Direct and simple. Does not require additional imports or setup. However, it’s only applicable to bytes and bytearrays, not other data types.
  • Method 2: Using binascii.hexlify. Robust and part of the standard library, suitable for network and storage. Requires decoding from bytes to string explicitely, which is an additional step.
  • Method 3: Using format() and join(). Flexible and customizable. Ideal for scenarios where more control is needed over the formatting. It is slightly more verbose and complex compared to the hex() method.
  • Method 4: Using bytearray and hex(). Offers the same convenience as the hex() method but is applicable for mutable bytearrays. Appropriate for when working with data streams that can be modified.
  • Bonus Method 5: Using the % Operator. Compact, but potentially less readable. Best for those with a background in C or similar languages where such formatting is common.