Rapid Answer: The following one-liner calculates the MD5 from the string 'hello world':
import hashlib as h;print(h.md5(b'hello world').hexdigest())
Background: MD5 message-digest is a vulnerable cryptographic algorithm to map a string to a 128-bit hash value. You can use it as a checksum on a given text to ensure that the message hasn’t been corrupted. However, you shouldn’t use it as a protection against malicious corruption due to its vulnerability. With modern hardware and algorithms, it’s easy to crack!
Problem: How to generate an MD5 sum from a string?
Example: Say, you have the following string text:
text = 'hello world'
And you want to convert it to the MD5 hash value:
5eb63bbbe01eeed093cb22bb8f5acdc3
We’ll discuss some methods to accomplish this next.
Method 1: hashlib.md5() — Multi-Liner
The hashlib library provides a function md5() that creates an object that can calculate the hash value of a given text for you via the method update():
# Method 1: hashlib.md5()
import hashlib
m = hashlib.md5()
text = 'hello world'
m.update(text.encode('utf-8'))
print(m.hexdigest())
# 5eb63bbbe01eeed093cb22bb8f5acdc3Make sure to encode the string as a Unicode string with the string.encode('utf-8') method. Otherwise, Python will throw an error.
Method 2: hashlib.md5() — Trivial One-Liner
As a one-liner, the code looks unreadable:
# Method 2: One-Liner
import hashlib; m = hashlib.md5(); m.update(text.encode('utf-8'));print(m.hexdigest())
# 5eb63bbbe01eeed093cb22bb8f5acdc3We used the standard technique to one-linerize flat code snippets without indented code blocks. Learn more in our related tutorial.
Related Tutorial: How to One-Linerize Code?
Method 3: Improved One-Liner
You can slightly improve the code by using the b'...' string instead of the encode() function to make it a Unicode string:
# Method 3: One-Liner import hashlib as h;print(h.md5(b'hello world').hexdigest()) # 5eb63bbbe01eeed093cb22bb8f5acdc3
I also initialized the md5 object with the Unicode string directly rather than using the update() method. The one-liner now has minimum number of characters—I don’t think it can be made even more concise! 😉
👉 Recommended Tutorial: How to Generate a Password Hash in Python?
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