How to Use a Spam Checker to Test Your Email Deliverability

Published October 12, 2024 · Updated August 9, 2026 · Email Security

A spam or email score checker tests whether your email will land in the inbox or the junk folder before you send to your whole list — a quick, essential step before any important send. It scores your content, authentication, and sending reputation, then flags exactly what to fix.

What it measures

Content signals — spammy words, all-caps, image-heavy layouts.
Authentication — SPF, DKIM, and DMARC results.
Reputation — whether your sending IP or domain is blacklisted.
Technical setup — reverse DNS, broken HTML, missing text parts, bad links.

How to run a test

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

Tip: Most low scores come from authentication and IP reputation, not wording. Fix SPF/DKIM/DMARC and send from a clean, reputable IP first — a two-minute spam check before a big send routinely saves a campaign from the junk folder.

Building the habit into your workflow
The senders who benefit most from a spam checker are the ones who make it a fixed step, not an occasional one — run it right after final proofreading and right before hitting send on anything going to more than a handful of people, so it catches issues while they are still one click away from fixing.
Note: Save your last few spam-check reports somewhere handy — comparing a new result against your own recent history is often more useful than the raw score alone.
A quick habit worth building: run a spam check the same way every time, using the same checklist, so results are genuinely comparable send over send rather than testing differently each time you remember to do it.
Related reading: Set up DKIM, SPF & DMARC · Email warmup guide · What is SMTP relay

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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 to your list.

What causes email to be marked as spam?

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

How do I improve my email score?

Fix authentication (SPF/DKIM/DMARC), send from a reputable dedicated IP, clean your list, and avoid spam-trigger content and formatting.