How to check if email address is valid?
Sending out emails to addresses that don’t exist, are spelt wrong, or are governed by the wrong type of mailbox, can create all sorts of unwanted problems for email marketers.

What we aim to show in this article is how to validate email addresses and just how easy, accurate, and cost-effecting using a service like Bouncer is as your email checker over the different manual options.
Your data is clean and protected, your lists stay in optimum health, and the returns from your campaigns stand the best possible chances of achieving the results you need.
Why should I check if an email address is valid?
Before we look at the ways you can check if an email address is valid, we need to take a look at the reasons you should be carrying out those checks in the first place.
- Reputation
- Deliverability
- Accuracy
- Performance
If you skip the validation of your email lists, you’re heading for troubled waters. Every year the number of email addresses that are scrapped or deactivated stands at over 20%. Failing to validate the addresses in your lists regularly could mean you’re heading for an automatic increase of 20–25% in your bounce rates.
Bounce rates that high will damage your sender reputation.
A poor sender reputation leads to poor deliverability—with campaigns landing in spam folders instead of inboxes. They won’t do you any good in there, so your chances of conversions, leads and sales will drop off the scale.
With the accuracy of your email addresses and campaigns failing, all you can expect is poor performance and weak results.
Reasons you shouldn’t send a test email to check an address’s authenticity
The simplest way to check if an email address is valid is to send a test email. Simple, huh? If your test hard-bounces, the address isn’t authentic and needs removing from your list.
So, what’s wrong with that?
The more emails you test that way, the more hard bounces you’ll receive. As those hard bounces add up, even without sending out campaign messages, they’ll damage your address reputation.
If it’s enough to get you added to the spam lists, it’s going to affect your deliverability, and in turn, your sending and campaign metrics.
The only way to use this method without it impacting your data is to set up a dummy email account from a different domain. That’s if you really want to pursue this method as an option, but you shouldn’t.
Additionally, you will just send spam messages to your recipients!
There are much easier and more effective methods of validating your addresses.
How to ping the server to validate an email address
One way to check if an email address is valid without sending an email is to ping the mail server.
You’ll need to use a console app to do this. It’s an accurate test, but it’s longwinded, technical, and overly time-consuming for more than a few addresses.
1. First, you’ll need the MX record from the domain’s DNS server. You do this by using a lookup command in your console app. Once you’ve accessed the list of mail exchanger MX records, you want the one with the highest priority—and that’s the one with the lowest preference value.
2. Validate the address via SMTP. Again, using your console app and the appropriate commands, connect to the email server via the MX record previously located, establish an SMTP handshake, specify the email address that needs validating, and finally perform its validation.
3. View your results. You will receive a ‘250 OK’ message for a valid address or the following message for a fake address: ‘The email account that you tried to reach does not exist. Please try double-checking the recipient’s email address for typos or unnecessary spaces’.
As we said, this is a long-winded process that requires a more than a basic level of expertise. It’s useful if you only have one or two addresses to validate, but if you’ve got a long mailing list of addresses to validate, it’s really not a practical option.
Using an email verification tool or service
Instead of checking each email address manually, resulting in hours of wasted time and effort, choosing a reliable and efficient service to do the hard work for you should be a no-brainer.
With Bouncer’s fully automated all-in-one tool, you can uncover all of the elements in your validation checklist to find out which emails have:
- Inactive email addresses
- Invalid email addresses
- Disposable email addresses
- Catch-all email addresses
- Role-based email addresses
- Bad syntax
- Free email domains
- Valid MX records
You’d find it almost impossible to check each of these features manually, and with our tool, it’s all wrapped up into a neat user-friendly interface, all at the click of a button.
But what does each of those options mean, and are they really necessary?
Inactive or invalid email addresses
Our software will carry out an automated email address ping to validate the status of each address. This is also known as SMPT authentication and works similarly to how we described the process when carried out manually—only much, much faster.
Disposable email addresses
A disposable email address is one designed for a specific purpose and then destroyed or deleted. Temporary email addresses provide nothing but hard bounces, and you know what that adds up to.
Catch all addresses
A catch-all address recovers emails that have been sent to a recipient where no specific mailbox exists.
Emails delivered to catch-all mailboxes aren’t likely to appear in front of someone directly interested in your product. Finding an address created for a catch-all account, you can make an educated decision on whether it has any value to you or not.
Role-based email addresses
Role-based addresses (think: [email protected]…, [email protected]…, or [email protected]…) aren’t aimed at a specific recipient, but a department and are unlikely to result in sales and conversions.
Also, by sending to an address aimed at a group of recipients, there’s far more chance that one of them will find your information irrelevant and send it straight to their spam folder.
For these reasons alone, they’re not always the right addresses for your marketing campaigns.
Syntax validation
Email syntax is how the address is constructed. Every email address is made up of 2 parts: the local and domain sections.
The local part is the information provided before the @ symbol, and the domain is what comes after it. For example, [email protected], where name is the local part and provider.co.uk is the domain.
The local part can include letters and numbers in upper or lower case. It can also include a range of special characters including !#$%&’*+-/=?^_`{|}~ and also the dot. However, you can’t use the dot consecutively (two of them together).
The domain part can also include upper and lower case letters and numbers and the hyphen. However, you can’t use the hyphen consecutively either (two of them together).
The main issues users have with email address syntax is a misspelling or incorrectly typed details. It’s clumsy to weaken your data lists and miss healthy ROI opportunities with valid addresses, only inputted incorrectly.
Free email domains
A validation tool also checks for email accounts that use a free email domain. Although many users of Gmail, Yahoo and other free service providers are genuine, with clear intentions, the quality of a recipient with a registered business domain is higher than that of those without.
MX record checks
The MX record provides details of the mail server used by the domain. Checking the domain’s MX record guarantees authentic email servers are in operation for the address and is one of the most vital parts of email validation.
What are the benefits of validating email lists?
Your lists will remain in the best health
Weeding out the addresses that organically become inactive each year is only the start. Your lists’ health will regularly be impacted by workers changing jobs, switching email service providers, or rebranding their business—accounting for too many hard bounces.
Reduced hard bounce rates
Regularly validation of your lists will keep your bounce rate low and email deliverability high. Hard bounces are damaging to your email reputation, which needs protecting at all costs.
It keeps deliverability high
With a strong email reputation, more of your messages will reach your recipient’s inboxes. Keeping out of spam folders promotes better click-through rates and conversions.
Increased conversions
Email marketing, especially to an opted in and healthy database is a proven strategy for a high ROI. Validating customer data ensure the deliverability of your message, creating valuable opportunities for sales and conversions.
Elevation of the brand profile
Engaging with your audience, one signed up to your service or already bought from you will strengthen your customer relationships. As long as the information you provide is relevant and of interest, email marketing is one of the best methods for repeat sales.
Without a clean database, high deliverability, and a strong email reputation, you’re not allowing yourself the best chances of reaching the inboxes you need to.
Email verification can only lead to better business
By showing you how to verify email address and the importance of clean data, we hope you can see the value in adhering to these best-practices.
The quality and presentation of your campaigns are wasted if they don’t even reach the inboxes and recipients they’re designed for.