How to convert an int to a hex string?

Hex conversion using String Formatting

Different approaches exist in Python when it comes to formatting strings. Let's take a look.

%-Style formatting:

hex_format = "%0.2X" % 255
print(hex_format)  # "FF", nice and clean!
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.format() and f-strings:

For lowercase hexadecimal:

hex_formatted = "{:02x}".format(255)
print(hex_formatted)  # "ff", small yet mighty!
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For uppercase hexadecimal using f-strings:

hex_fstring = f"{255:02X}"
print(hex_fstring)  # "FF", louder for the folks in the back!
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Controlling the Width and Padding

Maintaining control over width and padding in hexadecimal string representations strikes a winning balance of precision and readability.

Padding with zeroes:

# Using format()
padded_hex = format(255, '0>4X')
print(padded_hex)  # "00FF"

# Using an f-string
padded_fstring = f"{255:04x}"
print(padded_fstring)  # "00ff"
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Setting minimum width:

# Padding with enough zeroes to reach min width, but no '0x' prefix
min_width = "{:0>4x}".format(255)
print(min_width)  # "00ff"

# Now with a '0x' prefix
min_width_prefix = "0x{:0>4x}".format(255)
print(min_width_prefix)  # "0x00ff"
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Handling Large Numbers and the Role of chr()

Though chr() is related to converting integers to single character strings, for hexadecimal conversions it might not be your first port of call.

chr() with hex values:

For the ASCII value of a hexadecimal number within 255:

char_repr = chr(65)
hex_repr = format(ord(char_repr), 'x')
print(char_repr, hex_repr)  # "A 41", ASCII in disguise!
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When dealing with big numbers:

For integers beyond 255, hex() is your friend:

large_hex = format(4096, 'x')
print(large_hex)  # "1000", now that's what I call a large number!
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Navigating the ‘0x’ Prefix

The "0x" prefix signifies a hexadecimal number. Its visibility depends on your needs.

Without the 0x:

no_prefix_hex = hex(255)[2:]
print(no_prefix_hex)  # "ff", you've lost the glasses!
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With the 0x:

with_prefix_hex = "0x" + format(255, 'x')
print(with_prefix_hex)  # "0xff", visibility is key!
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