Get 20% OFF for your first month with the Starter Plan – Start today 🎉
Table of contents

Email Deliverability Test : How To Do It Right to Skyrocket your Deliverability in 2024

damien ceo mailreach
Damien Brenelière
Co-Founder @ MailReach & Email Deliverability Expert

Regularly running a deliverability test is one of the best practices to avoid the spam filters and improve your deliverability. At MailReach, we’ve seen that most of the time, deliverability testing is often done in an incomplete or biased way. In this article, we’ll cover how to properly run a deliverability test and check if your email will land in spam, categories or inbox.

deliverability test | how to do it right to raise your inbox placement

email deliverability test : intro

Intro & announcement : MailReach’s free deliverability test is now live.

Just before you go further in this article, we’re thrilled to announce that after months of development and fine tuning, we have finally released our free email spam test.

It has been developed and optimized with much love and passion to give you the most reliable spam score and deliverability check.

This deliverability test, combined to our email warm up service, offers a very effective and global cold email deliverability solution.

Because, yes, as you’ll understand it by reading this article, most deliverability tests are biased and not reliable today.

Good reading.

email deliverability test : advices

Email Deliverability test : it must be done in real sending conditions

We’ve seen so many times people run deliverability tests and wonder why their results are so different than the reality of their campaign statistics.

Do you know why?

Because most people are not aware that their sending tool alone can make them land in spam.

It’s not just about the email content or the reputation of the domain / IP. Sometimes it can just be the tracking domain automatically added in your email’s HTML by your email sending tool.

For further info about this, check our article How to Prevent Emails From Going to Spam.

In all cases, when doing a deliverability test, you need to send your email exactly as if you were emailing your real target.

That means, when doing a deliverability test :

  • Use your email sending service to send your test email
  • Send the exact same content you plan to send to your recipients
  • If you have personalization variables (e.g. “First Name”, “Company”), then replace them with values (e.g. “Franck”, “AB Consulting”). But of course, don’t take the risk of using potential spam words or it will screw your results.

email deliverability test : advices

Email Deliverability test : it has to done by sending your email to several inboxes

To know where your email will land, there’s only one way that really reflect the reality of your deliverability : sending your email to a significant number of inboxes and see where it lands. Period.

Why do we say this?

Because we often see people saying “Hey, I don’t understand, my emails are landing in spam but I have 10/10 on Mail-Tester.

Breaking news : a lot of people have 10/10 on Mail-Tester and land totally in spam.


Because Mail-Tester does not tell your where your email lands. It’s mainly here to scan your email and see if you respect the best practices.

According to us, using can be relevant to check if you’re in any blacklist, if your DNS records have been properly set up, etc.

But keep in mind that the best way to know your real deliverability and test your email for spam is by sending your email in real conditions to inboxes and check where it lands.

email deliverability test : advices

Email Deliverability test : it should be done towards the inbox providers used by your recipients

This one answers a very common problem we see nearly everyday at MailReach : a lot of people run deliverability tests and base their results on email providers that are not used by their real recipients.

It can totally bias the results since email providers don’t filter email the same way. And even inside Google, there are differences of spam filtering between addresses and paid Gmail (G Workspace). Same for Microsoft between addresses and paid Outlook (Office 365).

Let us explain that.

Let’s say you’re in the B2B area. The market share of email providers in B2B is around 60% for Google Workspace and 40% for Microsoft Office 365 (source : SuiteGuides).

This simply means that your recipients are either on Google Workspace or Office 365.

Thus, it’s really important to focus on these mailboxes when doing a deliverability test.

When testing your deliverability, if you land in inbox for all Google Workspace and Office 365 mailboxes, but are landing in spam in addresses, that doesn’t mean you’re doing bad.

For example, Gmail could recognize that your sending a B2B email to a address (generally used for B2C) and put it in spam because that’s not consistent according to their “rules”.

In all cases, we recommend that when doing a deliverability test, focus on the inbox services used by your recipients.

MailReach is compatible with any inbox / SMTP

No items found.

Frequently Asked Questions about running a deliverability test

What is a deliverability test?

A deliverability test is a way to measure the deliverability of your emails.

It’s usually done by sending an email to a list of several inboxes (the best option) or to a single address (this way can give poorer results).

The deliverability testing tool will then analyze your email and give you information in order to improve your deliverability.

A good deliverability test tells you where your email land on different inbox providers and checks several elements such as blacklists, DNS records, links, etc.

The result of a deliverability test is usually a score which helps you measure your efforts in order to improve it.

How do you run a deliverability test?

To run a deliverability test, you can use a deliverability testing tool like MailReach email spam test or another one. There are usually two options of doing it :

– Send an email to a given list of different inboxes. This is the most reliable way of testing your deliverability since you send directly from your address to the final inboxes.

– Send an email to a single inbox that redirects to several inboxes. We don’t recommend this option as it can bias the results of your deliverability test since it’s not done in the exact same conditions as if you were sending directly from your address.

Once you have sent your email, you receive your result with your score and improvements you can do.

What are the best tools for email deliverability testing?

The best tool for email deliverability testing has to be reliable, non biased, relevant and helpful.

To meet these requirements, the email spam checker tool should allow you to :

– Send your email to a list of inboxes instead of sending to a single address that redirects your email to several inboxes behind. This is crucial to avoid biasing your results. A good deliverability test is done in real sending conditions.

– Send your email to inboxes on different inbox providers and on the most important ones.

Filter your results depending if you target personal or professional inboxes. The big providers such as Google and Microsoft can easily understand if you talk business to a personal inbox and put you in spam. You need to check your deliverability on the inbox type you target. If you only target professionals, don’t look at personal inboxes.

Unfortunately, there are no multiple tools that meet these criteria, MailReach Spam Checker is the only one :

More resources for your deliverability

Made with ❤️ and 🥖 in Paris, France 🇫🇷