How the test works
- 1
Request it with your work email
Name, company and the address you send from. We reply from a person, not a sequence.
- 2
Your email is scored, then sent
The subject line and body are scored for the spam signals filters check, the way the Email Template Analyzer does it. Then the message is sent and its placement recorded at every major provider.
- 3
You get the result per provider
Inbox, promotions or spam at each provider, with the content findings, by email. If one provider is the problem, you will see which, and that changes the fix.
What each provider's decision is based on
- Gmail and Google Workspace. Engagement history first: whether people open, reply to, archive or report your mail, and the domain's standing in Postmaster Tools. Then authentication (SPF, DKIM, DMARC) and the spam rate, which Google's sender guidelines ask you to keep under 0.1%. Gmail is also the provider with a Promotions tab, so a Gmail result has three outcomes where the others have two.
- Microsoft 365 and Outlook.com. Sender reputation weighs more heavily than at Google, per IP and per domain, with complaint and trap data visible to senders in SNDS. Since May 2025 Microsoft rejects high-volume senders that fail SPF, DKIM or DMARC outright rather than junking them.
- Yahoo. Authentication, the complaint feedback loop and volume patterns; Yahoo defers mail it finds suspicious rather than rejecting it, so a Yahoo problem often shows as delay before it shows as spam.
The fix path, by outcome
- Spam at one provider, inbox at the rest. A reputation problem at that provider, not a content problem. This is the PostNitro pattern: around half of its Google mail in spam, everything else fine, and warming took Google from 67% to 100% in 11 days.
- Spam everywhere. Check the gates first: the domain reputation checker for blacklists and authentication, and the auth checker against the providers' rules. A domain that passes both and still lands in spam everywhere has a reputation to rebuild.
- Promotions at Gmail. For a B2C sender, the normal fight; for a cold sender, a sign the message reads as marketing. MailStrike's seed lists are built for the first case.
- Inbox everywhere, low replies. Placement is not your problem. The list or the copy is, and the content findings in the result are where to start.
How this differs from mail-tester and MxToolbox
mail-tester scores a single message for content and authentication issues and returns a number out of ten. It is a good pre-flight check and it does not tell you which folder the message reached at any provider. MxToolbox checks DNS records and blacklists, which are gates, not outcomes. A placement test measures the outcome those tools try to predict. Run the pre-flight checks, then measure.
Questions about the deliverability test
How do I test whether my emails are going to spam?
Send the email to inboxes whose folders you can read, at every provider your recipients use, and record where it landed. That is a placement test. Open rates cannot tell you, because a message in spam is rarely opened and a message in the inbox is often prefetched without being read. The Free Deliverability Test runs the placement test for you and reports inbox, promotions or spam per provider.
Is the email deliverability test free?
Yes. You sign up with a work email so we can send the results; no card and no plan are needed. The same placement tests are included in every MailStrike warming plan for ongoing use.
What does the test cover?
Two things. Your email is scored for the spam signals filters check (the subject line and body, the way the Email Template Analyzer scores them), and it is sent and reported provider by provider: inbox, promotions or spam at every major provider. The results arrive by email.
Does the test show the Gmail Promotions tab?
Yes. Promotions is reported as its own column, separate from spam. For a cold sender a Promotions result is unusual and worth understanding; for a newsletter or ecommerce sender it is the normal battleground, and it is the column most tests leave out.
How is this different from mail-tester or MxToolbox?
mail-tester scores one message for content and authentication problems and gives it a number; it does not tell you which folder the message landed in. MxToolbox checks DNS records and blacklists. Both are useful and neither measures placement. A placement test measures the outcome the other tools try to predict.