Question 1

What is scrypt?

Accepted Answer

Scrypt is a password-based key derivation function (KDF) designed by Colin Percival in 2009. It deliberately requires a large amount of memory, making it expensive for attackers to perform large-scale custom hardware attacks (ASICs, GPUs). Scrypt is used by Litecoin, Dogecoin and many password managers.

Question 2

What parameters should I use for scrypt?

Accepted Answer

Common defaults are N=16384 (2^14), r=8, p=1. For interactive logins, N=32768 (2^15) is recommended. Litecoin uses N=1024, r=1, p=1. Higher N values significantly increase memory usage and computation time. N must be a power of 2.

Question 3

Is my password sent to a server?

Accepted Answer

No. All scrypt key derivation runs entirely in your browser using the scrypt-js library. Your password never leaves your device.

Question 4

What is the difference between scrypt and Argon2?

Accepted Answer

Scrypt was the original memory-hard KDF (2009). Argon2 (2015) is its successor and the PHC winner, offering side-channel resistance (Argon2i) and more tunable parallelism. For new projects in 2025+, Argon2id is generally recommended over scrypt, but scrypt remains widely used and supported.