Email Header Analyser
Paste an email header or upload an .eml or .msg file to check how the message travelled, whether the sender passed authentication, and whether Microsoft 365 spotted any warning signs.
Everything runs in your browser. Your email headers are not uploaded, stored or sent to Black Swan.
Email header analyser
Paste raw email headers or drop in an email file to check the delivery path, authentication results and common spoofing signs. The output is written for real people, not just mail admins.
Email security next steps
Checking the header is only the start
An email header can show useful warning signs, but it does not protect the inbox on its own. These pages explain the extra layers that help stop phishing, account compromise, data loss and Microsoft 365 attacks.
Business Email Security
A practical overview of email security for small businesses, including phishing protection, spoofing risks and Microsoft 365 email defence.
Read the guide →Avanan Email Security
Protect Microsoft 365 and Google Workspace inboxes from phishing, malicious links, suspicious attachments and account takeover attempts.
Explore Avanan →Huntress ITDR
Watch for identity-based threats in Microsoft 365, including suspicious logins, risky inbox rules and signs that an account may already be compromised.
View Huntress ITDR →Microsoft 365 Cloud Backup
Back up Microsoft 365 mailboxes, OneDrive, SharePoint and Teams so deleted, encrypted or compromised data can be recovered.
See cloud backup →DMARC, SPF and DKIM
Improve domain authentication and reduce the chance of criminals sending emails that appear to come from your business.
Improve authentication →Phishing Awareness Training
Help staff spot suspicious emails, links and requests without blame, jargon or scare tactics.
Support your team →Microsoft 365 Security Posture
Check risky settings, weak configurations and Microsoft 365 security gaps before they turn into avoidable problems.
Check Microsoft 365 →Password Manager
Reduce password reuse, improve shared password handling and make it easier for staff to use strong, unique passwords.
View Keeper →Need help with an email?
If something looks suspicious and you are not sure what to do next, book a quick call and we can talk it through.
Book a free call →Tip: if the analyser flags a suspicious message, do not reply, click links or open attachments. Use the reporting options above, then check whether the same sender, subject or domain has reached anyone else in the business.
Meet Kevin: Founder of Black Swan
Concerned about cyber security? Need advice or a tailor-made quote? Kevin is here to help you!
From actionable advice to helping you to see where you could be at risk, Kevin will help you to get your business on a path that is secure-by-design and ready for the unthinkable.
Ready to replace sleepless nights with peace of mind? It all starts with an informal chat!
Either schedule a call by selecting a suitable date and time on the calendar or by clicking the button below to send us a message.
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