If you want to make sure your email marketing campaign is working, or if you want to improve the security of your internal emails, you’ll need email testing tools to help you get the job done.

The trouble is, with so many different types of email testing tools available, it can be hard to know where to begin.

In this guide, we’ll define and segment the different types of email testing, then list some of the most popular and most effective email testing tools you can use depending on your purposes.

What Is Email Testing?

Let’s start by defining email testing. Email testing can happen in a few different ways, but it’s also centered on evaluating emails for certain qualities; sometimes, those qualities pertain to security, while other times, they pertain to effectiveness.

Let’s take a look:

  • Email phishing and security testing. How secure is your company’s email? A single phishing attack can devastate your business, and you may never see it coming—that is, unless you use an email phishing testing tool to proactively detect and correct for the vulnerability. With email phishing and security testing, you can prevent phishing schemes and maintain the integrity of your internal systems.
  • Email deliverability and integrity testing. You can also test emails to maximize the chance that they will reach your intended audience. This typically includes testing in a wide variety of different areas. For example, some tools provide you with an HTML inbox rendering test, showing you how your email will be displayed in your recipients’ inboxes – including responsive design testing, for those recipients who read emails on a mobile device. Most email testing tools include a spam test, helping you evaluate whether or not your email may be flagged as spam. It may also test the internal links of your email, to make sure they all work.
  • Email success evaluation (AB testing). Marketers and salespeople want to maximize the effectiveness of their emails, and the best way to do that is through AB testing. There are great tools available for this, enabling you to tweak individual variables and see how they play with your audience.

Email Phishing Testing Tools

Let’s start with an assortment of email phishing simulation and testing tools you can use to improve your internal email security:

1. Gophish.

gophish - email testing tools

Gophish is an open-source phishing framework designed to reduce your vulnerability to phishing schemes. With it, you can build out different email phishing templates, send them to specific targets, and track your results, measuring the number of emails opened, links clicked, and forms submitted. You can install it for free.

2. Infosec IQ.

infoseciq - email testing tools

Infosec IQ offers a free phishing risk test that allows you to test your business’s susceptibility to phishing scams in just 24 hours. And if you’re interested in something more robust, you can use its PhishSim tool to run a full-scale campaign, relying on more than 1,000 phishing templates.

3. Phishing Frenzy.

phishing frenzy - email testing tools

It sounds like a mobile game, but Phishing Frenzy is actually an open source email phishing testing program, built on Ruby on Rails. You’ll need some familiarity with Linux and programming to get it to work, but if you have the right professionals on your team, you can use this to conduct thorough penetration testing for your organization.

4. King Phisher.

king phisher - email testing tools

Also available on GitHub is King Fisher, from SecureState. It’s an even more robust tool designed to help you design and run multiple email phishing tests simultaneously. With it, you’ll be able to get location data on your phished users, and view in-depth reports on the success of your attempts.

5. LUCY Security.

lucy - email testing tools

If you’re concerned about security in your organization, LUCY Security offers more than just an email phishing testing tool (though it offers that as well). With its services, you’ll get access to attack simulations across email and a variety of other channels. You’ll also get access to employee training and progress measurement, so you can grow as an organization.

Tools for Testing Email Deliverability

If email marketing or email-based sales are a bigger concern than your internal email security, you’ll be more interested to learn about the tools designed to help you test and evaluate your outgoing email blasts.

These are some of the best:

6. Mailchimp.


One of the best-known names in the email marketing world is Mailchimp. With both free and paid options, you can use Mailchimp to manage your email lists, design emails, and send them out—but not without testing them first! Mailchimp has several built-in tools to help you test your emails before you send them, including evaluating their spam score and previewing their designs.

7. Constant Contact.


The same is true for Constant Contact—one of the most robust email marketing tools available. Constant Contact offers thousands of templates and recommendations for how to create the perfect email campaign. And like Mailchimp, there’s no shortage of internal testing tools you can use to make sure your emails will be sent (and seen) properly.

8. Pabbly.

pabbly - email testing tools

Pabbly is a specialist tool that’s designed to improve email deliverability by getting rid of unwanted and obsolete email addresses on a given list. With just a few clicks, you can thoroughly test your email list and remove things like duplicates, inactive domains, and invalid addresses.

9. Reputation Authority.

reputationauthority - email testing tools

Have you ever wondered how many “good” or “bad” emails you’ve sent in the past? Reputation Authority will help you do it. With this tool, you’ll be able to evaluate your domain and dig into your reputation, determining whether your messages have had a positive or negative impact on your brand.

10. Postmark.


Postmark is a super simple tool that allows you to copy and paste your email’s code into an online interface. From there, you can preview your email and examine different variations. You can also check its spam score and make adjustments as necessary.

11. DataValidation.


DataValidation is more concerned with testing your email list than your actual email, but it’s still important. The app guarantees you’ll deliver 99 percent of your emails after using its list cleaning service. You’ll get a thorough breakdown of active and inactive email addresses, which you can then act on before you send your next blast.

12. Mail-Tester.


From MailPoet comes Mail-Tester, a tool designed to make it easy to evaluate your email for spam-related red flags. With it, you’ll be able to check for SPF and DKIM records, keywords that trigger spam indicators, and several other measurements. It’s also a convenient way to see if you’ve been blacklisted as a sender by any major email clients.

13. Mailtrap.


Mailtrap offers several email tests in the same place; with it, you can preview test your email, check your HTML with various email clients, determine your spam score, and more. Everything is done on a fake server, so you never have to worry about accidentally sending out a test email to real people.

14. NeverBounce.


NeverBounce is another email list testing tool. After using it, you’ll get a detailed report of how clean (or cluttered) your email list is, and you’ll get the chance to prepare your list for a live send.

15. Clearout.io.


There’s also Clearout, an email validation and verification service that promises 98 percent accuracy (or higher). It’s one of the most efficient and most reliable email verification services around—and it’s also easy to use.

16. SendForensics.


SendForensics contains a number of testing tools designed to help you improve your email deliverability. With it, you’ll be able to look at your sender score, preview the content of your email, and make improvements to get past the most common types of spam filters.

Email Preview Testing Tools

Your recipients read your emails on devices of all shapes and sizes, so it’s important to ensure that your email renders correctly across them! Use these tools to ensure they do:

17. Drip.


Adding to the list of all-in-one email marketing tools is Drip, which is designed to help marketers construct and manage automated drip email campaigns. But again, you’ll have access to multiple built-in tools for testing your emails before they get sent out.

18. GetResponse.


GetResponse offers testing for 25 of the most popular email clients. It also comes with a variety of other tools for your email marketing campaign, including email automation, templates for landing pages, and free webinars so you can learn more.

19. Litmus.


One of the most popular email testing tools available is Litmus, in part because it’s used by major corporations all over the world. With Litmus, you’ll be able to preview your email in many different clients and contexts, then change your code on the fly to see how your changes are reflected in the final product.

20. Email Preview Services.

emailpreviewservices - email testing tools

Take a guess what Email Preview Services allows you to do. It’s a tool meant to help you evaluate your code through the lenses of different email clients and platforms. Quickly and easily, you’ll be able to see how your email will appear to various people on your email list—and take action if there’s something that needs to be corrected before you send.

21. Email on Acid.


One of the most thorough email testing tools available, Email on Acid provides email preview testing with more than 70 different clients and devices. You can test your email with an endless combination of configurations to make sure it’s not going to appear broken for anybody.

22. HTML Email Check.


If you’re looking for a simple, free, and quick tool to check your HTML, XHTML, or CSS markup, HTML Email Check is for you. As an added bonus, you can use it to validate the links in your email, check images, and evaluate accessibility.

23. SubjectLine.

subjectline email testing tool

With SubjectLine, you can test your email’s subject line—both in terms of its spam score and in terms of its potential open rate. After using it, you’ll have a clearer picture of your subject line’s value, and hopefully, a direction on how to improve.

Email AB Testing Tools

AB testing involves creating multiple versions of the same asset, in this case an email: you’ll have an “A” version and a “B” version. You can launch both and compare their effectiveness against each other, objectively determining which variables are most important in your campaign.

Many of the email testing tools we’ve already listed also have some capacity for AB testing. But beyond those, here are some popular tools that either specialize in or excel at email AB testing:

24. Hubspot AB Testing Kit.


Hubspot’s “Complete A/B Testing Kit” is a combination of tools designed to help you brainstorm ideas for AB testing, build AB tests, and of course, measure and analyze the results of your AB email tests. It’s very intuitive if you’re just getting started.

25. Intercom.


One of the best-known CRM and marketing automation platforms online, Intercom also offers everything you need to plan, conduct, and analyze your AB email tests. It’s what we use here at EmailAnalytics!

26. Optimizely.


Optimizely is an experimentation platform designed to help you AB test your marketing campaigns, regardless of which channels you use. You’ll be able to run tests for emails, advertisements, web designs, and more.

27. AB Tasty.


AB Tasty offers a series of tools designed for experimentation, which allow you to create AB tests, split tests, multivariate tests, and more. You’ll also get access to in-depth reports to analyze your results.

Are you interested in learning more about how you or your team members use email on a daily basis? You may need a tool like EmailAnalytics.

EmailAnalytics connects to your Gmail account with a couple of clicks; from there, you can take a deep dive to learn your average response time, the number of emails you send and receive per day, your top senders and recipients, and more. Sign up for a free trial today, and get a closer look at the data visuals that can help you and your team members be better emailers!