How to Use a Spam Checker to Test Your Email Deliverability

Published October 12, 2024 · Updated July 21, 2026 · Email Security

A spam checker tests whether your email will land in the inbox or the junk folder - a quick, essential step before any important send. It flags what triggers filters so you can fix it first. Here is how to use a spam checker to test your email deliverability.

What a spam checker looks at

Content signals - spammy words, all-caps, image-heavy layouts.
Authentication - SPF, DKIM, and DMARC results.
Blacklists - whether your IP or domain is listed.
Formatting - broken HTML, missing text parts, bad links.

How to run a test

Send your campaign to the spam checker's test address, then review the report. Fix each flagged issue, re-test, and only then send to your list.

Do it every time: a two-minute spam check before a big send routinely saves a campaign from the junk folder. Make it a habit.

Reach the inbox

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Frequently asked questions

How do I check if my email is spam?

Send it to a spam checker's test address and review the report on content, authentication, blacklists, and formatting - then fix the flags before sending.

What causes email to be marked spam?

Failed authentication, a poor IP, spammy content, and blacklisting. Fix SPF/DKIM/DMARC and send from a clean dedicated IP.