PyCryptodome¶

PyCryptodome is a self-contained Python package of low-level cryptographic primitives, for Python 3.9 and newer. It needs no system libraries: install it with pip install pycryptodome.

What do you want to do?¶

I want to…	Recommended	Guide
Encrypt data with a secret key	AES-GCM	Encrypt data with a secret key
Encrypt data with a password	scrypt + AES-GCM	Work with passwords
Store and check users’ passwords	bcrypt	Work with passwords
Encrypt data for a recipient’s public key	HPKE	Encrypt data for a recipient’s public key
Sign data, or verify a signature	Ed25519	Sign data and verify signatures
Compute a hash of data or of a file	SHA-256	Hash data and authenticate messages
Authenticate a message with a secret key (MAC)	HMAC-SHA256	Hash data and authenticate messages
Generate, save, and load keys	PEM files (PKCS#8)	Generate, save, and load keys
Agree on a secret key with another party	ECDH (P-256) + HKDF	Generate, save, and load keys

For instance, this is how to encrypt and authenticate a message with AES in GCM mode, and then decrypt it (see Encrypt data with a secret key for the details):

from Crypto.Cipher import AES
from Crypto.Random import get_random_bytes

key = get_random_bytes(32)
nonce = get_random_bytes(12)
cipher = AES.new(key, AES.MODE_GCM, nonce=nonce)
ciphertext, tag = cipher.encrypt_and_digest(b"Attack at dawn")

# The receiver needs the key, the nonce, the ciphertext and the tag
cipher = AES.new(key, AES.MODE_GCM, nonce=nonce)
plaintext = cipher.decrypt_and_verify(ciphertext, tag)

Where to go next¶

Guides, for the common tasks, step by step.
API documentation, for all the algorithms and their parameters, grouped by package.
Installation, for the details of the installation.
Frequently Asked Questions, for the most frequent questions.