How to choose an Email validation solution


We already know the benefits of the validating the email addresses in real time. The next question is how to choose the email validation solution and what should be our selection criteria.

Some of the evaluation criteria we are going to focus on are:
1. Pricing
2. Correctness
3. Latency
4. Security
5. Additional information about an email address

1. Pricing – Luckily there are lots of services providers in this space which makes it really competitive. There are lots of old services as well as plenty of new entrants in the market. It is quite interesting to see the number of service providers who entered the space after Weblegit. The pricing usually has two components, one is dependent on the size of the company and the second is the cost for the infrastructure. If done correctly/carefully the cost of operations is pretty linear compared to the number of emails validated. Based on our own experience it should not cost you more than half a penny to validate one email address (With our architecture and algorithms we have been able to bring it down to a quarter of a penny). Bulk validations should even be cheaper. Unless someone is selling those validated email addresses somewhere else they need to make some money.

2. Correctness – Email validation is a hard problem to solve for a couple of reasons. Firstly not everything in the email world is homogenous. Different mail servers (gmail, yahoo, aol) have different policies and behavior. To make things more interesting there is a segment called as accept all mailboxes where only the domain name for email matters. So if someone claims to validate 100% of the email addresses then that should be treated as a red flag. However for all practical purposes its possible to achieve the correctness between 97%- 99% if it is done correctly.

3. Latency – If you are looking to use the email validation on your website or integrate with the API’s then latency should be really important. At Weblegit we have worked really hard to reach sub-second latency almost in all the cases. This is also a reason why we also provide the execution time in the API response to give you an idea of how long did it take to execute. On average it takes around 30ms – 250ms for almost all of the email addresses to validate.

4. Security – It is a major concern because an email is a client and if your validation service storing that in his database then it’s a potential loss because they can use them against you through your competitors. So make sure that they don’t store it.

5. Additional information about an email address – What additional information apart from the authentication of an email you are getting. Like

email String Email Address being validated
score Integer The score ranges from 0 t0 5 and indicates deliverability confidence. Anything less than 2 is non-deliverable.
disposable Boolean Indicates if the email is disposable
role Boolean True if the email is for a role like admin, contact, etc
valid Boolean Indicates that the email has valid syntax
catch_all Boolean True if email belong to catch all mail server
smtp_connection Boolean True if SMTP connection was successful
valid_format Boolean True if the syntax is valid
execution_time Long Total execution time in milliseconds