Yes. You can verify any @Mailbox.org address in real time with a direct SMTP handshake that provides 99.7% accuracy. Mailbox.org is operated by Heinlein Support GmbH, runs 4 mail servers, enforces 2 of 3 authentication standards, and is currently responding to SMTP.
Every check returns one of three clear outcomes so you know exactly what to do with the address.
The mailbox exists and accepts mail. Send with confidence, the address is deliverable.
The mailbox does not exist, is disposable, or will hard-bounce. Remove it to protect your sender reputation.
The server is catch-all or greylisting, so existence cannot be confirmed. Send selectively and watch engagement.
mailbox.org publishes 4 MX records. The primary mail exchanger is mx1.mailbox.org, hosted by mailbox.org, and it is currently reachable and answering SMTP. Mail is routed through these servers in priority order, lowest number first.
| Priority | Hostname | IP | Status |
|---|---|---|---|
| 10 | mx1.mailbox.org | 80.241.60.212 | Reachable |
| 10 | mx2.mailbox.org | 80.241.60.215 | Reachable |
| 20 | mx3.mailbox.org | 80.241.60.216 | Reachable |
| 50 | mx-n.mailbox.org | 91.198.250.17 | Reachable |
220 mx1.mailbox.org ESMTP PostfixYes. mailbox.org is a valid email provider, operated by Heinlein Support GmbH. Addresses are persistent and real mail reaches a genuine recipient. Individual mailboxes still go stale, so verify each one before you send.
A live SMTP handshake connects to Mailbox.org's mail server and asks whether the mailbox exists using the RCPT TO command, without ever transmitting a message. The recipient never sees the check.
Each address runs through 30+ checks including SMTP existence, catch-all detection, role-account filtering, and disposable matching. The same engine has verified billions of addresses since 2012.
Every unverified address is a gamble. Here is what happens when you skip verification and mail a list that has not been cleaned.
Free inboxes get abandoned constantly. Verification drops the dead mailbox.org mailboxes before you mail them.
Mistyped mailbox.org addresses fail a real SMTP check, so they never turn into a hard bounce.
A clean list keeps your bounce rate low, and a low bounce rate is what protects inbox placement on a big send.
Mailing only live mailbox.org addresses raises every rate that matters: opens, clicks, and replies.
Mailbox.org is Heinlein Support GmbH, registered through CPS-Datensysteme GmbH and first seen Jan 6, 2014.
mailbox.org is a German privacy-focused email service operated by Heinlein Support GmbH, based in Berlin. The service offers paid email accounts with strong encryption, calendar, contacts, cloud storage, and video conferencing, all hosted in German data centers under strict privacy standards.
mailbox.org implements SPF, DKIM, and DMARC authentication. The service supports PGP encryption, uses German-hosted servers exclusively, and complies with German and EU GDPR data protection. Mailbox.org is certified by the BSI (German Federal Office for Information Security).
The mailbox.org mail servers enforce recipient verification and reject invalid addresses. The domain does not function as catch-all. Security-focused filtering protects the privacy-conscious user base.
For delivery to mailbox.org, authenticate with SPF, DKIM, and DMARC. Mailbox.org users are security-conscious. German providers apply strict filtering. Well-authenticated messages deliver reliably.
Upload a CSV or TXT list of Mailbox.org addresses to the bulk email verifier. Every address runs through a live SMTP handshake plus catch-all, role-account and disposable detection, and you download a clean list when processing completes. For real-time checks at signup, use the real-time email verification API.
CSV or TXT with one email per line. No formatting needed.
Each Mailbox.org address is checked with a live server handshake.
Get a verified list with status codes, risk flags, and catch-all detection.
Pay as you go. No subscriptions, and credits never expire.
Everything about verifying email at this domain.
Yes, mailbox.org is a valid email domain operated by Heinlein Support GmbH in Berlin, Germany. It is a privacy-focused paid email service.
No, mailbox.org is a permanent paid email service with strong privacy protections under German law.
Mailbox.org operates its own mail servers in Germany with full encryption and privacy-focused infrastructure.
Yes, with consent and GDPR compliance. Mailbox.org users are privacy-conscious and expect transparent communication practices.
Mailbox.org addresses can be verified via SMTP. As a paid service, addresses are typically valid and actively maintained.
Upload a CSV or TXT list to the bulk email verifier. Every address runs through 30+ checks including SMTP existence, catch-all detection, role-account, and disposable matching. Processing time depends on list size.
99.7% accurate using a direct SMTP handshake with mailbox.org's mail servers, the same engine that has verified billions of addresses since 2012.
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