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Will Gmail, Yahoo and Microsoft accept your bulk email?

Enter your sending domain. We check SPF, DKIM and DMARC against the rules Gmail and Yahoo have applied since 2024 and Microsoft applies from 2025, and give you the exact DNS record to fix anything that fails.

What to check
Advanced (optional)

Free, no login. We store the domain and result for 30 days, and a test email for 7 days — see our privacy policy.

What this checks, and why it matters

In February 2024, Gmail and Yahoo started requiring bulk senders — anyone sending roughly 5,000 or more messages a day to their users — to publish working SPF, DKIM and DMARC records, and to include a one-click unsubscribe link. Microsoft rolled out an equivalent requirement for its own bulk-sender programme from May 2025. Mail that fails these checks is increasingly rejected outright, not just filtered to spam.

SPF (Sender Policy Framework) lists which servers are allowed to send email claiming to be from your domain. DKIM (DomainKeys Identified Mail) adds a cryptographic signature to each message, so a receiver can tell it wasn't altered in transit and really did come from a server you authorised. DMARC (Domain-based Message Authentication, Reporting and Conformance) ties the two together: it tells receivers what to do with mail that fails SPF or DKIM, and asks for reports on who's sending as your domain.

We check all three live against your domain's DNS, work out which of the 2024/2025 rules you meet, and show you the exact record to publish for anything that's missing — in plain English, not RFC references. Fixing DNS should help your mail reach the inbox; it isn't a guarantee, because inbox placement also depends on your content and sending reputation, which only a real test message can show.

DNS can't show everything. Send a test email and we check the message as it actually arrives: whether its DKIM signature and bounce address line up with your From: domain (the usual reason DMARC fails for mail sent through a service), whether it carries a one-click unsubscribe header, the sending server's reverse DNS, a check against a limited set of public blocklists, a spam filter score, and how well its HTML is supported across email apps.

Frequently asked questions

+ Is this free?
Yes. Enter a domain and get the full report, no account and no email address needed.
+ Do I need to give you my email address?
No. You can see the whole report without giving us anything. We only ask if you'd like the report emailed to you as well, and we store nothing until you tick that box.
+ Will fixing these records get me into the inbox?
It should help. Gmail, Yahoo and Microsoft require SPF, DKIM and DMARC from bulk senders, so without them mail is increasingly rejected outright. Passing all three removes that block, but inbox placement also depends on your content and sending reputation, which we can't see from DNS alone.
+ What's the difference between SPF, DKIM and DMARC?
SPF lists the servers allowed to send as your domain. DKIM signs each message so receivers can confirm it wasn't altered. DMARC tells receivers what to do when a message fails either check, and asks for reports on who's sending as you.
+ I pasted a bounce message and it didn't explain the code — why?
We recognise the enhanced status codes and phrases Gmail, Microsoft and Yahoo use most often. If yours isn't one of them, the codes are usually documented by the provider that sent the bounce; feel free to get in touch and we'll look at adding it.
+ How long do you keep my result?
The report stays at its private link for 30 days, then it's deleted. If you asked us to email it to you, we keep that email address until you unsubscribe.
+ Why send a test email as well as checking DNS?
DNS shows what your domain publishes. A real message shows what your sending service actually does: which domain signs it, whether it lines up with your From: address, whether it has a one-click unsubscribe header, and how a spam filter scores it. The most common DMARC failure, mail signed by the sending service's own domain, only shows up in a real message.
+ Which blocklists do you check?
A limited set of public lists: SpamCop (bl.spamcop.net), PSBL (psbl.surriel.com) and DroneBL (dnsbl.dronebl.org). We do not check Spamhaus or commercial lists, so a clean result here does not mean the server is on no list at all.
+ What happens to the test email I send?
It goes to our own test server, not to a person. We keep the message there for 7 days so the report can be built, then delete it. The report, which includes the sending server's address and the authentication results, stays at its private link for 30 days.

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