Email Spam Word Checker & Linter.
Test your cold outreach and marketing emails before sending. Detect 150+ spam trigger words, assess subject line impact, and optimize reading grade level.
What this spam checker evaluates:
Enter your subject line and message body on the left, then click Analyze Deliverability to inspect:
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Email Spam Testing FAQs.
Understand how Bayesian spam filters, keyword heuristics, and subscriber engagement impact your inbox placement.
How do spam filters score my email copy?
Modern spam filters (such as SpamAssassin, Microsoft EOP, and Google Postmaster AI) scan your email for trigger phrases, link density, excessive capitalization, and HTML code anomalies. If your cumulative penalty score exceeds the gateway threshold, the message is routed to the Junk/Spam folder.
What is an ideal reading level for cold outreach?
Cold email engagement data shows that emails written at a 5th to 7th grade reading level (Flesch Reading Ease score of 65–85) receive up to 36% more replies than complex, formal copy. Keeping sentences short and punchy reduces cognitive load.
Can clean email copy still go to spam?
Yes. Copy is only one of three deliverability pillars. If your domain lacks DNS authentication (SPF, DKIM, DMARC) or if you send to unverified, invalid email addresses that bounce, mailbox providers will flag your sending IP regardless of your text score.
How many links should I include in a cold email?
For initial cold emails, we recommend including at most 1 link (or zero links in the very first touchpoint). Having multiple links dramatically increases spam suspicion and lowers reply rates.
Clean your entire email list with zero bounces.
Sortwell checks addresses the way a mail server would — live SMTP handshake, syntax, MX verification, and spamtrap detection.