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Subject line checker tool

Use the subject line checker to test your email subject line for spam words!

Check for Spam Words

Here’s the problem with spammy email subject lines…

All email service providers have their respective systems for spam email detection. Their goal is to catch obvious bad actors who are looking to take advantage of unsuspecting email users with spammy, deceptive content to trick them or steal their data.

A spam word checker is a typical detection form. And your subject lines can trigger spam email detection automatically, relegating your emails to Spam.

A man with a concerned expression holds his hands to his face as he looks at his laptop and sees that his email has gone to Spam.

How the email subject line checker works

Our free email subject line tool compares the text found in your subject line against a collection of well-known spam trigger words. Email service providers aren’t looking to block legitimate contact like yours, so they make no secret of what words or phrases can trigger their filters.

Our subject line/spam word checker highlights any known spam words and gives you a ratio of how many there are compared to safe-for-use words or phrases. Think of it like this: the more spam trigger words that are present, the more likely it is to impact email deliverabilityⓘ.

Examples of spam trigger words:

  • ✔ Cheap
  • ✔ Debt
  • ✔ Eliminate debt
  • ✔ Trial Offer
  • ✔ Prize
  • ✔ You won!
  • ✔ Bonus
  • ✔ Read this
  • ✔ Prescription
  • ✔ Invest
Check out this extensive list of spam wordsTest my email subject line
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Best practices for creating safe and effective email subject lines

So – what are email marketing best practices when it comes to subject lines?

Keep these email marketing tips in mind.

Be direct

Be direct and descriptive

Everyone wants to include a little bit of clickbait in their subject lines. A bit of intrigue is acceptable (and practical!), but recipients should always have an understanding of what’s inside your email.

Readers should know from your email subject lines if they’re checking out an offer, an announcement, an update, or some other description that helps them understand how the email benefits them. Email service providers will also be checking to help them avoid spam emails.

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Warmup

Still hitting Spam after using our free email subject line tool? It could be your sender reputation.

Warm up your email domain by allowing us to automatically send emails for you and provide positive email engagement that looks and feels authentic to ESPs.

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Inbox Placement Testing

Take Spam email detection to the next level by testing your campaign with 20+ well-known mail providers, including Gmail/G-Suite, Outlook, Yahoo, and more.

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Email Server Testing

Ensure that an email server configuration error isn’t preventing you from reaching the inbox.

Run 200+ tests on your email server testⓘ today free.

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Blacklist Monitoring

If you’re still hitting Spam with these email marketing tips, you need to make sure your domain isn’t on a blacklist/blocklist.

Create a free account today and start monitoring your domain at no cost.

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DMARC monitoring

Securing your email and authenticating your identity will keep emails out of spam and improve email open rates.

Set up a new DMARC policy today and monitor all outgoing emails sent from your business domain.

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Free email verifier

Avoid bounces and risky emails. Check any email address with our free email validationⓘ and verification tool.

Find out if your contact’s address is valid and any other relevant information, including domain information and social data, when available.

Try the free verifier

Want to learn more? Check out our handy Email Deliverability Toolkit guide!

Avoid spam email with our free email subject line tool

Getting rid of spammy subject lines is easy. Click below to head back up and use our email subject line checker – and bookmark this page for frequent use!

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The ZeroBounce logo with lines branching out to its free account benefits: 1 inbox placement test, 1 email server test, 100 email verification credits, 1 blacklist monitor, and 10 email finder queries.
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