E-mail header analyser
Check for free whether an e-mail is genuine: sender, route of the message and SPF, DKIM and DMARC – right in your browser, nothing is transmitted.
No data is stored. The analysis runs entirely in your own browser – the header is neither transmitted nor stored.
Where do I find the e-mail header?
- Outlook (Windows)
- Open the message by double-clicking → File → Properties → select and copy the whole “Internet headers” field.
- New Outlook / Outlook on the web
- Open the message → “…” (More actions) → View → View message details.
- Gmail
- Open the message → “⋮” → Show original → copy the top part up to the first empty line.
- Apple Mail
- Select the message → View → Message → All Headers.
- Thunderbird
- Select the message → View → Message Source (Ctrl+U).
Background
What the header reveals about an e-mail.
Every e-mail carries a hidden header with its route across the servers and the receiving system’s checks. It shows whether the displayed sender is genuine.
// 01
SPF
Defines which servers may send on behalf of a domain. “fail” means the sending server is not authorised.
// 02
DKIM
A digital signature by the sender. If it is valid, the message was not altered in transit.
// 03
DMARC
Links SPF and DKIM to the visible sender address. “fail” is a strong sign of a spoofed message.
Suspicious e-mail in your company?
For phishing, fake invoices or doubts about e-mail security, a short review helps – including SPF, DKIM and DMARC for your own domain.