Email spam checker

A spam checker analyzes email subject lines and content for characteristics that spam filters use to block or flag emails. It looks for spam trigger words, excessive capitalization, suspicious punctuation, and other signals that inbox providers associate with spam. Running your email through a spam checker before sending helps improve deliverability.

Emails land in spam for many reasons: spam trigger words in the subject or body, poor sender reputation, missing SPF/DKIM/DMARC authentication, sending to purchased or unengaged lists with high bounce rates, excessive links or images, HTML-to-text ratio issues, or being reported as spam by previous recipients. Authentication issues and sender reputation are the most common causes.

Use a spam checker tool like this one to analyze your subject line and content. Also check your email authentication setup—verify that SPF, DKIM, and DMARC are correctly configured for your domain. Send test emails to spam testing services, and monitor your deliverability metrics (bounce rate, spam complaint rate) over time.

Spam trigger words are phrases commonly associated with spam emails. They include words like "free", "guaranteed", "act now", "click here", "make money", "winner", "prize", "urgent", and many others. Spam filters assign point values to these words, and emails exceeding a threshold score are flagged or blocked. Avoiding these words and using natural language improves deliverability.

Yes—email authentication (SPF, DKIM, DMARC) is critical. Without proper authentication, receiving mail servers have no way to verify your email is legitimate, making it more likely to be treated as spam. Since 2024, Gmail and Yahoo require DMARC authentication for bulk senders. Properly authenticated emails with a clean sender reputation reach the inbox far more reliably than unauthenticated emails.