Verify emails in Ruby with Verifly

Email verification in Ruby and Rails

Ruby on Rails made email a first-class citizen of web apps, and with it came a first-class problem: the addresses users type in are frequently wrong, disposable, or dead. Rails validations and gems like validates_email_format_of check that an address is syntactically plausible, but syntax is not existence. A perfectly formatted address can point at a mailbox that was deleted, a domain that only issues throwaway addresses, or a role inbox nobody monitors — and you only discover it when the mail bounces.

Verifly turns that into a single HTTP call, and Ruby's standard library already has everything you need. net/http and json ship with the language, so there is no gem to add to your Gemfile and keep updated. You build a request, set a Bearer header, and JSON.parse the response into a hash with a result key of deliverable, undeliverable, or risky plus disposable, role, catch-all, and smtp flags. That maps naturally onto Ruby idioms — a case statement on the result, or a select block over an array of results.

The pay-as-you-go pricing suits both a Rails monolith and a one-off rake task. From $2 per 1,000 checks down to $0.60 per 1,000 at volume, there is no seat to justify and no plan to pick. Self-register for 100 free credits with no card and no captcha, keep the vf_ key in Rails credentials or an ENV var, and reuse it across models, workers, and scripts.

Batch-verify an array of emails in Ruby

When you have a list, POST it to /verify/batch rather than looping the single endpoint. Send a JSON body with an emails array and parse back a results array in order, which you can filter and partition with Ruby's Enumerable methods. This is the right tool for a rake task cleaning an imported CSV or a Sidekiq job preparing a campaign list.

require 'net/http'
require 'json'

emails = ['ada@example.com', 'info@some-domain.com', 'noreply@disposable.tld']
uri = URI('https://verifly.email/api/v1/verify/batch')

req = Net::HTTP::Post.new(uri)
req['Authorization'] = 'Bearer vf_YOUR_KEY'
req['Content-Type'] = 'application/json'
req.body = { emails: emails }.to_json

res = Net::HTTP.start(uri.host, uri.port, use_ssl: true) { |h| h.request(req) }
results = JSON.parse(res.body)['results']

clean = results.select { |r| r['result'] == 'deliverable' }
puts "Keeping #{clean.size} of #{results.size}"
results.each do |r|
  puts "drop: #{r['email']} (#{r['result']})" if r['disposable'] || r['role']
end

Validate at signup in a Rails model

The best place to verify in a Rails app is right where a User is created. A custom validation or a before_save hook that calls Verifly — with a read timeout so a slow probe never stalls the request, and fail-open behaviour on error so signups survive an outage — lets you reject disposable addresses and flag undeliverable ones before the record is committed.

require 'net/http'
require 'json'

def email_ok?(email)
  uri = URI('https://verifly.email/api/v1/verify')
  uri.query = URI.encode_www_form(email: email)
  req = Net::HTTP::Get.new(uri)
  req['Authorization'] = 'Bearer vf_YOUR_KEY'

  res = Net::HTTP.start(uri.host, uri.port, use_ssl: true, read_timeout: 8) do |h|
    h.request(req)
  end
  data = JSON.parse(res.body)
  return false if data['disposable']
  data['result'] != 'undeliverable'
rescue StandardError
  true # fail open on network error
end