How to Decode Base64 Data String in Python

If you have data as Base64 String that you want to decode using Python, you can make use of the base64 module.

Let's take a look at it by an example.

Example:

import base64

base64_encoded_string = 'SGVsbG8gUHl0aG9uIQ=='
base64_decoded_bytes = base64.b64decode(base64_encoded_string)
base64_decoded_string = base64_decoded_bytes.decode('utf-8')

print(base64_decoded_string)

Output:

We have achieved this in two steps by using two methods from the base64 modules:

1. base64.b64decode(s, altchars=None, validate=False)

This method decodes the Base64-encoded bytes or ASCII string and returns the decoded data as bytes.

Parameters:

s: The Base64-encoded string or bytes to decode.
altchars (optional): An alternative set of characters used for the encoded string.
validate (optional): If True, perform additional validation checks on the input. Defaults to False.

Returns: The decoded data as bytes.

2. bytes.decode(encoding='utf-8', errors='strict')

This method decodes the bytes object using the specified encoding and returns a string.