Email service providers are working hard to improve their safety mechanisms, making it nearly impossible to break through if your reputation or email content are less than perfect. Spam filters – aka spam killer software – will block any suspicious emails from reaching the recipient.

There are several best practices you should follow:

  • Ensure proper email authentication and setup
  • Verify the emails on your list to avoid spam traps and minimize bounces
  • Get to know some of the trigger phrases or use spam words checker
  • Avoid links, images, and HTML elements in your emails
  • Always run a SMTP spam test before sending the email

The latter is probably the most important step here. A basic SMTP spam check will give you an understanding of the potential issues that get your emails blocked. Luckily, spam checking tools make it easy to do.

There are several spam checker sites – including the free ones – you should know.

  • is the most popular spam checker tool used by email marketers. It’s very easy to use with detailed instructions to fix any issues. It’s also one of the email spam checker tool online that are free to use.
  • Glock Apps is more than an email address spam checker, offering a bunch of useful tools for deliverability.
  • Kickbox offers email marketing spam checker as well as list verification or even deliverability consulting.
  • MxToolbox is another online email spam checker we recommend.

As you can see, there are plenty of options to check spam email score. You can pick any mail spam tester you like, just make sure it provides accurate results and comprehensive suggestions to fix any problems, following spam filter best practices.