CircleCI Gem Version

Covert makes your string securely obfuscated.


Add this line to your application's Gemfile:

gem 'covert'

And then execute:

$ bundle install

Or install it yourself as:

$ gem install covert



Covert.configure do |config|
  config.cipher_key = 'blah!'
  config.cipher = 'AES-256-CBC' # default
  config.hmac_key = 'blah!'
  config.hmac_digest = 'SHA256' # default


Covert.obfuscate('mystring') #=> "7hSfzDwp2JXZcieFpGCndA=="


Covert.unobfuscate('7hSfzDwp2JXZcieFpGCndA==') #=> "mystring"


Covert.hmac('hmac') #=> "13ca4d5b9cdc1485834a05d926913d919d3c83de29c99314a7dbccafdc8be8ac"


Comparison with gem obfuscate with Blowfish algo.

require 'obfuscate'
require 'covert'
require 'benchmark'
require 'securerandom'

Obfuscate.setup :salt => 'a very weak salt indead.'

Covert.configure do |config|
  config.cipher_key = 'blah!'

puts { |bm|
  ids = []"obfuscate x1000:") {
    1000.times { ids << Obfuscate.obfuscate( SecureRandom.uuid, {:mode => :block} ) }
  }"clarify x1000:") {
    ids.each { |id| Obfuscate.clarify( id, {:mode => :block} ) }

  ids = []"myobfuscate x1000:") {
    1000.times { ids << Covert.obfuscate(SecureRandom.uuid) }
  }"myclarify x1000:") {
    ids.each { |id| Covert.unobfuscate(id) }
                            user       system     total       real
Obfuscate.obfuscate x1000:  7.883860   0.044474   7.928334 (  7.944916)
Obfuscate.clarify   x1000:  7.841752   0.016152   7.857904 (  7.873886)
Covert.obfuscate    x1000:  0.011217   0.012656   0.023873 (  0.024485)
Covert.unobfuscate  x1000:  0.003891   0.000358   0.004249 (  0.004359)


After checking out the repo, run bin/setup to install dependencies. Then, run rake test to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to


Bug reports and pull requests are welcome on GitHub at This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the code of conduct.


The gem is available as open source under the terms of the MIT License.

Code of Conduct

Everyone interacting in the Covert project's codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.