Spam Word Scanner

Why spam word scanning matters for email deliverability

Email spam filters don’t just check your sender reputation — they scan the content of your message for words and phrases that historically appear in spam campaigns. Gmail, Outlook, Yahoo Mail, and the filtering engines used by ESPs like Mailchimp, Klaviyo, and HubSpot all run some form of content analysis before deciding whether your email reaches the inbox, lands in spam, or gets blocked entirely.

The problem is that many legitimate marketing phrases — “guaranteed,” “act now,” “limited time” — are also the most common phrases in spam. Using even a handful of these in the wrong combination can push an otherwise clean email past a filter’s threshold. This is especially risky in subject lines, preheader text, and above-the-fold copy where filters place the most weight.

Scanning your email HTML before you send takes seconds and gives you the chance to rephrase flagged content before it costs you deliverability. A single high-severity trigger phrase can move your email from inbox to spam across a significant portion of your list.

How it works

1. Paste your email HTML into the editor above, or drag and drop an .html file.
2. Click “Scan for spam words.” The tool strips all HTML tags and scans the resulting plain text against the full word database.
3. Review flagged phrases sorted by severity — high-risk phrases first, then medium, then low. Not sure what a phrase flags on? See the full reference list below.
4. Rephrase or remove flagged content in your original HTML. “Buy now” → “Shop the collection.” “Guaranteed” → “Backed by our 30-day policy.”
5. Re-scan to confirm. Paste your revised HTML and run the scan again until no high-severity issues remain.

Frequently asked questions

What exactly is a spam trigger word?

A spam trigger word or phrase is a term that spam filters associate with unsolicited or deceptive email based on statistical patterns across millions of messages. Filters like SpamAssassin assign a numeric score to each hit — enough points and your email is classified as spam.

Do spam filters check the subject line separately?

Yes, and subject lines are weighted more heavily than body copy. This tool scans the full HTML you paste, so if your subject line is included in a preview text or preheader element, it will be caught. For best results, also manually review your subject line against the reference table below.

Why does “unsubscribe” show as a low-severity flag?

CAN-SPAM and GDPR both require an unsubscribe mechanism, so the word itself is expected in legitimate email. It only becomes a filter signal when it appears as the only trust indicator in an otherwise suspicious message. In a normal marketing email it is not a concern.

Does Gmail use a spam word list?

Gmail’s spam detection is primarily machine-learning-based and goes beyond simple word lists — it factors in sender reputation, engagement history, authentication (SPF, DKIM, DMARC), and content signals together. That said, high-spam-score content still contributes negatively, and reducing trigger language improves your content signal.

How many spam words is too many?

There is no universal threshold — filters combine content score with sender reputation and engagement data. A sender with strong reputation can get away with more than a new domain. As a rule: zero high-severity phrases, and no more than two or three medium-severity phrases in a single email.

Will removing spam words guarantee inbox delivery?

No. Content is one of several factors. Sender reputation, authentication records, list hygiene, and engagement rates all contribute. Spam word scanning is one layer of deliverability hygiene, not a complete solution.

Related tools

• CSS Inliner — Convert style blocks to inline styles for full ESP compatibility.
• HTML Minifier — Compress your email HTML to stay under Gmail’s 102KB clip limit.