password: Hashing and checking of passwords

[ bsd3, data, library ] [ Propose Tags ]

A library providing functionality for working with plain-text and hashed passwords with different types of algorithms.


Every supported hashing algorithm has its own module (e.g. Data.Password.Bcrypt) which exports its own hashPassword and checkPassword functions, as well as all the types and functions in this module. If you are not sure about the specifics of an algorithm you want to use, you can rest assured that by using the hashPassword function of the respective algorithm you are not making any big mistakes, security-wise.

Of course, if you know what you're doing and you want more fine-grained control over the hashing function, you can adjust it using the hashPasswordWithParams function of the respective algorithm.


Generally, the most "secure" algorithm is believed to be Argon2, then scrypt, then bcrypt, and lastly PBKDF2. bcrypt and PBKDF2 are the most established algorithms, so they have been tried and tested, though they both lack a memory cost, and therefore have a greater vulnerability to specialized hardware attacks.

When choosing an algorithm, and you have no idea which to pick, just go for bcrypt if your password does not need the highest security possible. It's still a fine way for hashing passwords, and the cost is easily adjustable if needed. If your needs do require stronger protection, you should find someone who can advise you on this topic. (And if you're already knowledgeable enough, you know what to do)

[Skip to Readme]


Manual Flags


Compile with Argon2 support?


Compile with bcrypt support?


Use the [crypton] library as the cryptographic backend.


Use the [cryptonite] library as the cryptographic backend. (Does nothing until a future major version)


Compile with PBKDF2 support?


Compile with scrypt support?


Use -f <flag> to enable a flag, or -f -<flag> to disable that flag. More info


Note: This package has metadata revisions in the cabal description newer than included in the tarball. To unpack the package including the revisions, use 'cabal get'.

Maintainer's Corner

Package maintainers

For package maintainers and hackage trustees


  • No Candidates
Versions [RSS],,,,,,,,,,,,,,
Change log
Dependencies base (>=4.9 && <5), base64 (>=0.3 && <1.1), bytestring (>=0.9 && <0.13), cryptonite (>=0.15.1 && <0.31), memory (<1), password-types (<2), template-haskell, text (>=1.2.2 && <3) [details]
License BSD-3-Clause
Copyright Copyright (c) Dennis Gosnell, 2019; Felix Paulusma, 2020
Author Dennis Gosnell, Felix Paulusma
Revised Revision 1 made by nideco at 2024-05-28T17:58:36Z
Category Data
Home page
Bug tracker
Source repo head: git clone
Uploaded by nideco at 2024-01-28T19:57:19Z
Distributions LTSHaskell:, NixOS:, Stackage:
Reverse Dependencies 2 direct, 1 indirect [details]
Downloads 4080 total (47 in the last 30 days)
Rating 2.25 (votes: 2) [estimated by Bayesian average]
Your Rating
  • λ
  • λ
  • λ
Status Docs uploaded by user
Build status unknown [no reports yet]

Readme for password-

[back to package description]


Build Status Hackage Stackage LTS Stackage Nightly BSD3 license

This library provides functions for working with passwords and password hashes in Haskell.

Currently supports the following algorithms:

  • PBKDF2
  • bcrypt
  • scrypt
  • Argon2

Also, see the password-instances package for instances for common typeclasses.