About Postwacht
Postwacht is a free German email deliverability tester. It analyses test emails and checks SPF, DKIM, DMARC, blocklists, MTA-STS, BIMI and SMTP. The goal is that you see why an email does not arrive and know what to do about it.
Operator
Postwacht is operated by Timo Kessel. Legal details are in the imprint (German). Contact: mail@postwacht.de.
Data and servers
- The servers are located in Germany.
- There are no third-party trackers. Our own usage measurement runs on our own server, without cookies and without IP addresses.
- What happens to test emails and how long they are kept is described in the privacy policy (German).
Costs
The email test, the tools and the open API are free. A free account adds daily monitoring of domains and DMARC report analysis.
What Postwacht is not
- No guarantee for the inbox: a good score means the technical setup is right. How a mailbox sorts an email is up to that mailbox.
- Not a consulting service: we show findings and instructions; you or your provider implement the changes.
- Not a source of legal advice.
How we check
The checks follow the standards (for example RFC 7208 for SPF, RFC 6376 for DKIM, RFC 7489 for DMARC, RFC 8461 for MTA-STS) and the requirements of the large mailbox providers. The limits of each tool are described on its page, for example in the DMARC study (German).