Domain Intelligence
Last Updated:

Gmx.de

Safe to Send

Gmx.de is operated by GMX Germany. The domain runs 2 mail exchanges and SMTP is responsive, with 2 of 3 authentication standards in place.

Safe to Send
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Live SMTP handshake against gmx.de mail servers. No email is sent. 10 free per day, no signup.

@gmx.de
No email sent No signup Real-time SMTP

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SOC 2 Type II GDPR CCPA 99.7% Accuracy
Disposable
No
Persistent addresses, not throwaway
SMTP Live
Yes
Mail server responds to SMTP handshake
MX Records
2
Mail exchangers

Mail Exchange (MX) Records for gmx.de Mail Exchange records. They tell other mail servers which hosts are responsible for receiving email at this domain, in priority order. Lower priority numbers are tried first.

2 RECORDS
#10
mx00.emig.gmx.net 212.227.15.9
Reachable
#10
mx01.emig.gmx.net 212.227.17.5
Reachable
SMTP Handshake Simple Mail Transfer Protocol. We open a live SMTP connection to the primary MX and read the greeting banner. A response confirms the mail server is alive and accepting connections. Responsive
BANNER220 gmx.net (mxgmx009) Nemesis ESMTP Service ready
Primary mail server accepted SMTP connection and returned a banner during the live audit.

gmx.de Email Authentication SPF · DKIM · DMARC

2/3 PASS
SPF Sender Policy Framework. A DNS record listing which servers are allowed to send mail for this domain. Receivers reject or flag mail from unauthorized servers. Pass
TXTv=spf1 redirect=_spf.gmx.net
Authorized senders are defined and pass SPF policy.
DKIM DomainKeys Identified Mail. The sending server cryptographically signs outbound mail with a private key, and receivers verify the signature using a public key in DNS. Missing
No DKIM signature detected on common selectors for gmx.de.
No DKIM signature was detected. Receivers cannot verify the integrity of outbound mail.
DMARC Domain-based Message Authentication, Reporting & Conformance. Tells receivers what to do when SPF or DKIM checks fail: none, quarantine, or reject. Quarantine
TXTv=DMARC1; p=quarantine; rua=mailto:dmarcreport@gmx.net
Receivers are instructed to quarantine (route to spam) any mail that fails SPF or DKIM.

gmx.de Domain Registration WHOIS · Nameservers · Registrar

WHOIS
Last UpdatedApril 19, 2016
TLD.de
Authoritative Nameservers (4)
  • ns-gmx.ui-dns.biz
  • ns-gmx.ui-dns.com
  • ns-gmx.ui-dns.de
  • ns-gmx.ui-dns.org
About this Domain

About gmx.de

gmx.de is the primary German domain for GMX (Global Message eXchange), one of Germany's most popular email and internet portal services. GMX is operated by 1&1 Mail and Media (a United Internet subsidiary) and serves tens of millions of users in Germany. The gmx.de domain is specifically tailored for the German market with localized content and services.

gmx.de supports robust SPF, DKIM, and DMARC authentication through United Internet's enterprise infrastructure. As a major email provider, GMX enforces strict authentication standards. Full alignment is required for consistent inbox placement.

The gmx.de mail servers perform thorough recipient validation, apply advanced spam filtering with machine learning classifiers, and enforce rate limiting. GMX actively monitors sender behavior and may block IPs with poor sending practices.

For delivery to gmx.de, ensure SPF and DKIM authentication, maintain clean lists with low bounce and complaint rates, and comply with German telecommunications law (TKG) and GDPR. GMX is strict about sender reputation, so gradual IP warmup and engagement-based sending are strongly recommended.

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Common Questions About gmx.de

Is gmx.de a disposable or temporary email provider?
No. gmx.de is not a disposable email provider. It is classified as ISP Email Provider operated by GMX Germany and addresses on gmx.de are persistent rather than throwaway. Mail sent to a valid gmx.de mailbox reaches a real recipient.
How do I verify if a gmx.de email address is valid?
The fastest way to verify a gmx.de email address is to use our free email checker. Enter any @gmx.de mailbox at the top of this page and our system performs a real-time SMTP handshake against gmx.de's mail servers, confirming whether the mailbox exists, is reachable, and is safe to send to. No email is ever delivered during the check.
Can I check if a gmx.de email exists without sending a message?
Yes. Our real-time email verification API connects directly to gmx.de's mail server, opens an SMTP session, and queries the mailbox using the RCPT TO command without ever transmitting an actual email. The server's response confirms whether the gmx.de mailbox is valid, full, or non-existent. The recipient never receives anything and never sees the check.
What are the MX records for gmx.de?
gmx.de currently publishes 2 mail exchange (MX) records. The primary MX is mx00.emig.gmx.net, which is the first server contacted when other mail systems try to deliver email to a gmx.de address. The full list with priorities and IP addresses is in the MX Records panel above. MX records tell sending servers where to route email for gmx.de.
Does gmx.de use SPF, DKIM, and DMARC email authentication?
gmx.de has 2 of the 3 standard email authentication records in place: SPF, and DMARC (policy: quarantine). Adding the missing layer(s) would tighten anti-spoofing protection and improve deliverability for legitimate gmx.de mail.
Why do emails to gmx.de bounce or get blocked?
Bounces from gmx.de usually fall into three buckets: the mailbox doesn't exist (5xx user unknown), the inbox is full, or your sending domain isn't authenticated to gmx.de's satisfaction. The fastest fix is to run each address through a free email verifier before you send, and to make sure your own SPF, DKIM, and DMARC are configured correctly so gmx.de's receivers trust you.
How can I verify a large list of gmx.de email addresses?
Our bulk email verifier accepts CSV or TXT uploads with thousands or millions of gmx.de addresses (or any mix of domains). Every address goes through 30+ checks including SMTP existence, gmx.de catch-all detection, role-account detection, and disposable-domain matching. Results typically come back within minutes and previously-failed addresses on your blacklist are reprocessed for free. For continuous high-volume needs, see our unlimited email verification API.
Is it safe to accept signups from gmx.de email addresses?
Yes, with normal hygiene. gmx.de is a legitimate email service and signups from @gmx.de behave like any other real user. Pipe each address through a real-time email verifier API at the moment of signup to catch typos and dead mailboxes, but there is no need to block gmx.de by default.
What email format does gmx.de use for usernames?
Most gmx.de mailboxes follow common patterns like first.last@gmx.de, firstinitiallast@gmx.de, or first@gmx.de, but the actual local-part rules depend on GMX Germany. The only reliable way to confirm whether a specific @gmx.de address exists is to run it through a free email verification tool. Guessing patterns will produce a high bounce rate and damage your sender reputation.
How is the gmx.de risk score calculated?
The 0-to-100 risk score for gmx.de combines disposable-domain classification, mail-server reachability, MX record presence and depth, SPF / DKIM / DMARC enforcement, DMARC policy strength, SMTP banner response, and domain age. Lower scores mean safer to send to. Disposable domains are pinned at the high end of the scale. The gmx.de score is recomputed on every audit so it always reflects the live state of the domain.
Is gmx.de a valid email domain?
Yes, gmx.de is a valid and active email domain operated by GMX (Global Message eXchange), one of Germany's most popular email services with tens of millions of users, run by United Internet.
Is gmx.de a disposable or temporary email service?
No, gmx.de is not a disposable or temporary email service. It is a permanent, mainstream email platform and one of the most widely used email domains in Germany.
What mail servers does gmx.de use?
gmx.de uses mail servers managed by United Internet/1&1 Mail and Media infrastructure. The MX records direct inbound email to GMX-operated gateways with advanced spam filtering and delivery systems.
Can I send marketing emails to gmx.de addresses?
You can send marketing emails to gmx.de addresses with valid opt-in consent. Authenticate with SPF and DKIM, comply with German telecom law and GDPR, maintain low complaint rates, and gradually warm up new sending IPs.
How do I verify a gmx.de email address?
You can verify a gmx.de email address using an email verification service that checks MX records and performs SMTP-level validation to confirm the mailbox is active and accepting messages.