Cold Email · · 6 min read

8 Best Email Tester & Validation Tools for Your Campaigns

Are you looking for the best email tester and validation tools to improve your campaigns? Email marketing is one of the most powerful ways to reach customers. 59% of marketers say email is their biggest source of ROI, and 87% use email marketing to disseminate their content.

email tester

For your emails to be effective, they must reach the intended recipient. That’s why email tester and validation tools are so important for marketers. These tools ensure your emails are sent to the right address and are not lost in the digital shuffle.

This article will cover:

  • Reasons you should regularly test emails
  • Best email tester tools for email validation
  • Best email tester tools for cleaning email lists
  • Best email warm-up tools

Why You Should Regularly Test Emails

The following are some of the main reasons why you should regularly test your emails:

Boost Deliverability

Email deliverability is one of the most critical aspects of successful email campaigns. Your efforts to engage customers are wasted if your emails don't reach their destination. If your deliverability rate decreases, so do your ROI and reputation with internet service providers.

Regular testing allows you to ensure that your emails reach their destination and improves email deliverability.

Reduce Bounce Rates

Bounce rates occur when your email is not accepted and sent back to the sender. Many issues, such as invalid email addresses or domain names, can cause these. Regular testing helps reduce bounce rates by identifying invalid emails before they are sent out.

Lower Costs

You can lower your sending costs by using email tester and validation tools. This is because you can avoid emailing invalid addresses, which wastes money and resources. You can also prevent the cost of blacklisting, which can occur when too many emails are sent out simultaneously. Your goal shouldn't be sending emails to as many people as possible but targeting the right audience.

Best Email Tester Tools for Email Validation

Now that you know why email testing is important, let’s look at the best tools or email validation and testing.

Preview My Email

preview my email
Preview My Email 

Used by marketers, designers, and developers, Preview My Email lets double-check your code before sending it out. You can also view your emails across 54 different email clients. It also allows you to identify and fix spam issues so your emails don’t get caught in spam filters. It runs your IP against the 50 most common industry backlists.

Preview My Email also offers screenshots of your email on all popular email applications. This way, you can quickly identify any design or layout issues.

Email on Acid

email on acid
Email on Acid

Email on Acid allows you to "Put your best email forward." Email on Acid is another popular email tester and validation tool. It offers real-time testing for more than 70 different applications and devices. It also tests your email against 23 spam filters to ensure that your emails reach their destination, and you can avoid wondering why are my emails going to spam.

Some of the other great features Email on Acid offers other great features: email previews, HTML click-to-fix editor, inbox placement testing, leading Email Verifications, Placement Testing, and reputation monitoring. Like Preview My Email, Email on Acid also offers email previews on the latest clients and devices to ensure a positive user experience.



Mailtrap is another powerful email tester and validator tool. It allows you to test emails, send emails, and monitor deliverability.

Its test emails feature allows you to inspect and debug emails, so you can ensure that your emails are sent correctly. Best part? The feature offers 20+ code integrations. With the send emails feature, you can send 10,000 emails per second, enjoy custom variables and headers, benefit from auto email warm-up, and more. All in all, Mailtrap is a great tool if you're looking for an all-in-one testing and validation solution.

Get Response

Get Response is an email tester and validator that offers email previews across 25 clients. The tool allows you to create automated email sequences, design and trigger action-based, deliver emails at the right time, and use SMTP-triggered emails to send receipts or reminders.

Creating visually-appealing emails can be time-consuming, and this is where Inbox Inspector comes in. It offers a drag-and-drop email creator that helps you create beautiful emails in minutes.

Best Email Tester Tools for Cleaning Email Lists

The following are the best tools for cleaning email lists:


Zero Bouce
Zero Bounce

ZeroBounce allows you to clean your email list in bulk within minutes.

The tool's email verifier allows you to reduce your bounce rate by getting rid of invalid, disposable, and spam-trap emails. What we love about ZeroBounce is that once your email list is clean, you can simply connect their email validation API to your signup and registration forms. This way, every new email you enter into your system is automatically validated.



Clearout is a bulk email verification tool that can help you clean and validate email lists quickly.

For quick email verification, all you have to do is copy and paste the email addresses from your list and let the email tester do its job. The email verifier offers 98% accurate results with detailed stats and delivery reports. The stats cover spam traps, soft bounce vs. hard bounce, disposable, etc.

Best Email Warm-Up Tools


instantly homepage

Instantly's goal is simple: to ensure that your emails don't land in the spam folder. Best part? The tool gives you an exact percentage of emails that land in the primary box.

Your goal as a sender is to get your emails into the inbox, and your sending reputation plays a massive role in this process. An email sender's reputation is like a credit score for email sending. The higher the score, the more likely an ISP will trust you and deliver your emails. Good thing Instantly helps you build and maintain a good sending reputation by interacting positively with your emails.



MailReach is an excellent email warm-up tool that helps you boost your sending reputation and prevent spam filters from blocking your emails.

The tool, on an everyday basis, positively interacts with your emails to improve your sending reputation and email deliverability. MailReach improves your sending reputation by starting conversations with your emails and ensuring your email gets positive interactions. MailReach is compatible with all the popular providers, is automated and easy to use, and offers real-time reporting.

Key Takeaways

Email testing and validation are essential to ensure your emails reach the right inboxes.

To recap:

  • If you're looking for an email validation tool, Preview My Email, Email on Acid, Mailtrap, and Inbox Inspector are great choices. They offer detailed email previews, automated testing processes, and email validation services.
  • ZeroBounce and Clearout offer reliable bulk email verification services for cleaning email lists. They allow you to reduce your bounce rate, identify invalid emails, and keep track of the validity of emails.
  • For warming up your email, Instantly and MailReach are two great options. They help you build a good sending reputation, interact positively with your emails, and prevent spam filters from blocking your emails.

For the best email warm-up experience, try Instantly. It helps you build and maintain a good sending reputation so your emails land in the right inboxes. Get started today!

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