Paste a raw header to inspect SPF, DKIM, DMARC, Reply-To, Return-Path, and routing clues without uploading email content.
Paste raw headers from a suspicious or transactional email. The analyzer runs locally in your browser and highlights authentication, routing, and alignment signals.
No obvious header warnings were detected in this sample.
Headers do not prove that an email is safe, but they help explain whether the sender domain was authenticated and whether visible sender fields match the technical envelope.
Every email carries metadata that records who claims to have sent it, which servers handled it on the way, and whether the sending domain was authenticated. This metadata is called the email header. Most mail clients hide it behind menus like "View source" or "Show original," but it is the most reliable place to look when you are trying to confirm whether a message is genuine, find why a transactional email landed in spam, or investigate a suspected phishing attempt.
The tool parses the header text locally in your browser and surfaces the fields that matter for security: Authentication-Results (SPF, DKIM, DMARC), From, Reply-To, Return-Path, and the Received chain. It compares the visible From domain with the Return-Path and Reply-To domains, flags unusually long routing paths, and gives you a quick verdict score so you can decide whether to trust links and attachments. Nothing is sent to a server.
SPF pass means the sending IP is authorized in the envelope domain's DNS. DKIM pass means the message was signed with a key the domain owner published, so the body was not modified in transit. DMARC pass means at least one of SPF or DKIM aligned with the visible From domain. A missing or fail result for any of the three is not proof of phishing on its own, but combined with mismatched Reply-To, unusual Received hops, or generic display names it is a strong signal to slow down.
In Gmail open the message, click the three-dot menu and choose "Show original." In Outlook on the web, open the message, click "More actions" and pick "View message source." In Apple Mail use View → Message → All Headers. Copy the entire block, paste it into the field above, and the analyzer will run instantly.
Use the SPF generator next when you are configuring a domain you control.
