A long-lived project that still receives updates
ActiveModel validation for email. Including MX lookup and disposable email blacklist


~> 2.0
>= 0
~> 12.3
~> 3.5


~> 2.5
 Project Readme


Gem Version

Validate emails with the help of the mail gem instead of some clunky regexp. Aditionally validate that the domain has a MX record. Optionally validate against a static list of disposable email services. Optionally validate that the email is not subaddressed (RFC5233).


There are lots of other gems and libraries that validates email addresses but most of them use some clunky regexp. I also saw a need to be able to validate that the email address is not coming from a "disposable email" provider.

Is it production ready?

Yes, it is used in several production apps.


Add this line to your application's Gemfile:

gem "valid_email2"

And then execute:

$ bundle

Or install it yourself as:

$ gem install valid_email2


Use with ActiveModel

If you just want to validate that it is a valid email address:

class User < ActiveRecord::Base
  validates :email, presence: true, 'valid_email_2/email': true

To validate that the domain has an MX record or A record:

validates :email, 'valid_email_2/email': { mx: true }

To validate strictly that the domain has an MX record:

validates :email, 'valid_email_2/email': { strict_mx: true }

strict_mx and mx both default to a 5 second timeout for DNS lookups. To override this timeout, specify a dns_timeout option:

validates :email, 'valid_email_2/email': { strict_mx: true, dns_timeout: 10 }

To validate that the domain is not a disposable email (checks domain and MX server):

validates :email, 'valid_email_2/email': { disposable: true }

To validate that the domain is not a disposable email (checks domain only, does not check MX server):

validates :email, 'valid_email_2/email': { disposable_domain: true }

To validate that the domain is not a disposable email or a disposable email (checks domain and MX server) but whitelisted (under config/whitelisted_email_domains.yml):

validates :email, 'valid_email_2/email': { disposable_with_whitelist: true }

To validate that the domain is not a disposable email or a disposable email (checks domain only, does not check MX server) but whitelisted (under config/whitelisted_email_domains.yml):

validates :email, 'valid_email_2/email': { disposable_domain_with_whitelist: true }

To validate that the domain is not blacklisted (under config/blacklisted_email_domains.yml):

validates :email, 'valid_email_2/email': { blacklist: true }

To validate that email is not subaddressed:

validates :email, 'valid_email_2/email': { disallow_subaddressing: true }

To validate that email does not contain a dot anywhere before the @:

validates :email, 'valid_email_2/email': { disallow_dotted: true }

To validate create your own custom message:

validates :email, 'valid_email_2/email': { message: "is not a valid email" }

To allow multiple addresses separated by comma:

validates :email, 'valid_email_2/email': { multiple: true }

All together:

validates :email, 'valid_email_2/email': { mx: true, disposable: true, disallow_subaddressing: true}

Note that this gem will let an empty email pass through so you will need to add presence: true if you require an email

Use without ActiveModel

address = ValidEmail2::Address.new("lisinge@gmail.com")
address.valid? => true
address.disposable? => false
address.valid_mx? => true
address.valid_strict_mx? => true
address.subaddressed? => false

Test environment

If you are validating mx then your specs will fail without an internet connection. It is a good idea to stub out that validation in your test environment.
Do so by adding this in your spec_helper:

config.before(:each) do
  allow_any_instance_of(ValidEmail2::Address).to receive_messages(
    valid_mx?: true,
    valid_strict_mx?: true,
    mx_server_is_in?: false


This gem is tested against currently supported Ruby and Rails versions. For an up to date list, check the build matrix in the workflow.

Upgrading to v3.0.0

In version v3.0.0 I decided to move and rename the config files from the vendor directory to the config directory. That means:

vendor/blacklist.yml -> config/blacklisted_email_domains.yml
vendor/whitelist.yml -> config/whitelisted_email_domains.yml

The disposable validation has been improved with a mx check. Apply the stub, as noted in the Test environment section, if your tests have slowed down or if they do not work without an internet connection.

Upgrading to v2.0.0

In version 1.0 of valid_email2 we only defined the email validator.
But since other gems also define a email validator this can cause some unintended behaviours and emails that shouldn't be valid are regarded valid because the wrong validator is used by rails.

So in version 2.0 we decided to deprecate using the email validator directly and instead define a valid_email_2/email validator to be sure that the correct validator gets used.

So this:

validates :email, email: { mx: true, disposable: true }

Becomes this:

validates :email, 'valid_email_2/email': { mx: true, disposable: true }


  1. Fork it
  2. Create your feature branch (git checkout -b my-new-feature)
  3. Commit your changes (git commit -am 'Add some feature')
  4. Push to the branch (git push origin my-new-feature)
  5. Create new Pull Request