In our quest for a cost-effective, straightforward, and efficient method to assess the quality of our newsletters, we developed our very own testing tool. We're excited to offer it for free through our web interface, allowing you to integrate our tests into your applications and whitelist our service by creating an account. As enthusiastic email software engineers, we generate a unique email address each time you visit our portal. To utilize our service, simply send a message from your preferred newsletter or email software to this newly generated address. After sending, click on the "check your score" button, and once we receive your message, our system will provide your spam score. Mail-tester will thoroughly examine your email, mail server, and sending IP, delivering a comprehensive report that outlines what is configured correctly and what requires attention. It's important to note that spam filters vary widely, meaning that while your email may pass through mail-tester, it might still be flagged in your personal office inbox due to different filtering criteria. Additionally, the final outcome can also be influenced by individual user preferences and settings. Therefore, it's advisable to conduct multiple tests to ensure deliverability across various platforms.