Email Deliverability Test

Check your email content for spam words, check your domain for DNS accuracy and blacklist listings, and monitor your email’s deliverability.

What is Email Deliverability?

While there is no universally accepted definition for “email deliverability,” it is essentially understood to mean the likelihood that your emails will reach your recipients’ primary inboxes.

SMTP and IMAP servers, bounce filters, spam/junk filters, and category filters (like Gmail’s tab system) are the gatekeepers that play a role in your email’s deliverability.

To improve deliverability, you must convince all of these gatekeepers that your emails are valid, relevant, and worth reading.

Table of Contents

Email Deliverability Best Practices

In order to maximize the chance that your emails will reach their intended recipients, ensure you are following these email deliverability best practices.

Technical Setup

Server/IP Reputation. Sending from a server/IP address with good reputation is a must. Big-name email hosts like Gmail, Outlook, Zoho, etc. will always be sending from trusted IP addresses.

However, some prefer to run their own email servers or use more cost-effective email hosts. Many times, the tradeoff is that these alternatives are on less trusted infrastructure. That means their IP addresses are more likely to be on blacklists or graylists, which will immediately reduce the deliverability of your emails.

Check the domain/IP tester above to make sure that your domain/IP address pass all blacklist checks.

DNS. Three TXT records are key to good email deliverability: SPF, DKIM, and DMARC. All of them are used to ensure that malicious users can’t spoof your email (steal your email identity) and send emails that appear to be from your address.

SPF (Sender Policy Framework) is a type of DNS record that specifies which IP addresses are permitted to send emails from their domain, and it helps prevent spam and phishing attacks. When receiving mail servers receive an email, they check the SPF record to verify that the sending server is authorized to send mail from that domain. If the sending server is not authorized, the email may be marked as spam or rejected altogether.

DKIM (DomainKeys Identified Mail) is another type of DNS record that adds a digital signature to email messages, allowing receiving mail servers to verify that the message came from the specified domain and that it has not been altered in transit. The DKIM signature provides an additional layer of security and helps prevent spoofing and phishing attacks. It also helps improve email deliverability by reducing the likelihood of legitimate emails being marked as spam.

DMARC (Domain-based Message Authentication, Reporting & Conformance) is a policy record that specifies how email receivers should handle messages that fail SPF or DKIM authentication checks. It provides domain owners with visibility into how their domain is being used for email, and it helps prevent fraudulent use of their domain for phishing and spam attacks. DMARC also provides guidance to receiving mail servers on how to handle messages that fail authentication checks, such as quarantining or rejecting them. Implementing DMARC can help improve email deliverability and protect a domain’s reputation.

Message Content

Spam Words. Spam/junk filters have sophisticated algorithms that are getting better and better. But avoiding spam words like “pharmacy” or “buy now” is the most important step. Use the Spam Word checker above to make sure your email content does not contain spam words.

HTML. Sending emails in plain text is best for deliverability, but that often isn’t possible. If you must send emails with HTML (to include images, for example), be sure to use as little HTML as possible.

Links. If your email contains a lot of links to various different sites, it is more likely to trip up the Categories filter.

Images. Similar to HTML, in general, including too many images makes it more likely that your email will trip spam/junk filters. Even open tracking images can decrease deliverability.

Headers. Algorithms like SpamAssassin will check your email’s headers. For example, the Received headers are used to identify the source of the email and to check for signs of email spoofing or phishing. The DKIM header is used to verify the email’s authenticity and to ensure that it has not been tampered with. The To header is used to determine if the email is sent to a large number of recipients or if the recipient is a known spam trap email address.

Email Activity

Sending Volume. Sending a large amount of email over a short period of time, rapid swings in the number of emails sent from day to day, starting to send too many emails too early – all of these are signs that email providers use to flag your emails as possible spam.

Email Engagement. Even if you’re doing everything else right, if you’re sending a lot of emails are aren’t being opened or replied to, email providers will start to catch on and become more likely to treat your emails as spam/junk.

Using a service like Boxward to improve your engagement and monitor your email’s reputation is an absolute necessity if your business is relying on email outreach.

Types of Email Deliverability Testers

There are a number of different types of email checkers, but most are limited to checking your email content/headers, and possibly your deliverability to a small collection of accounts.

Single Email Testers

These deliverability tests are run by emailing a particular email address. They will evaluate your single email for content and header errors that may decrease deliverability.

Good For:
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Bulk Email Testers

These tests are run by emailing a particular email address. They then forward your email to a variety of different inbox types.

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Email Warmup Tools

These tools allow you to connect your email for full email monitoring and deliverability reporting. They will automate sending and receiving to increase your email’s reputation and give you an accurate picture of how healthy your email is over time.

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Email Deliverability FAQs

Still have questions after testing your email deliverability?

Using a reputable email provider, setting up appropriate DNS records, writing non-spammy content, verifying email addresses on your list to prevent bounces, and warming up your email are all ways to improve your email deliverability.

Generally, the less you add, the better your deliverability will be. While it may be unavoidable at times, if you’re adding anything beyond plain text, do so judiciously.

A spam trap is an email address used by internet service providers (ISPs) to identify and block spammers. These email addresses are not used for legitimate communication and can result in blacklisting if they are included in email lists.

You can avoid sending emails to spam traps by using reputable email lists, removing inactive or invalid email addresses, and regularly cleaning your email list.

Sender reputation refers to the reputation of an email sender’s IP address and email domain. A good sender reputation is important for email deliverability, as ISPs are more likely to deliver emails from reputable senders to the recipient’s inbox.

Email warmup describes a process where your email is connected to a warmup network so that it can automatically send emails to other inboxes in the network, which are then automatically opened, replied to, and marked important. It increases the sender reputation of your email addresses.

Start Warming Up Your Email!

You could be losing sales right now with emails landing in junk