Free GMX, Web.de & T-Online Email Verifier
Validate @gmx.de, @gmx.net, @gmx.at, @gmx.ch, @web.de, and @t-online.de addresses with full United Internet (1&1 Mail & Media) and Deutsche Telekom SMTP compliance.
⚙️ Gmx Webde Email Verifier Telemetry Specs
GMX, Web.de & T-Online Live SMTP Handshake & MX Diagnostic
Supported domains: @gmx.de, @gmx.net, @gmx.at, @gmx.ch, @web.de & @t-online.de
| SMTP Code / Response | KaijuVerifier Verdict | Technical Meaning |
|---|---|---|
| 250 Requested mail action okay, completed | Valid DACH Mailbox | The GMX, Web.de, or T-Online inbox exists and is actively accepting messages. |
| 550 Requested action not taken: mailbox unavailable | Non-Existent / Deleted | The account does not exist or has been deactivated after prolonged inactivity. |
| 552 Quota exceeded (mailbox for user is full) | Web.de / GMX Storage Full | Free @web.de accounts have strict storage limits and frequently bounce with 552 Quota Exceeded. |
| 554 Transaction failed / Bad DNS PTR | Strict rDNS Policy | United Internet and Telekom require RFC-compliant reverse DNS (FCrDNS); handled natively by KaijuVerifier's EU SMTP nodes. |
How We Verify GMX, Web.de & T-Online (Germany / DACH) Addresses
Shared Reputation Across GMX, Web.de & 1&1 IONOS
In Germany, Austria, and Switzerland, over 50% of consumer inboxes run on United Internet (`emig.gmx.net` / `web.de`). Sending to unverified @gmx.de or @web.de addresses immediately triggers network-wide Postmaster blocks.
Catching Full Free-Tier @web.de Mailboxes (Code 552)
Legacy free @web.de accounts have historically tight storage quotas. KaijuVerifier distinguishes between permanently deleted accounts (550) and full mailboxes (552) so you can protect your DACH sender score.
Compliant Probing for mx00.t-online.de
Deutsche Telekom (`t-online.de`) enforces some of Europe's strictest FCrDNS and HELO checks. Our verification nodes maintain clean PTR alignment to verify @t-online.de leads accurately.
Verify Other Email Providers & Regional ISPs
Frequently Asked Questions — GMX, Web.de & T-Online Verification
Why are @gmx.de, @web.de, and @t-online.de so critical for German email marketing?
Together, Web.de, GMX, and T-Online represent more than 60% of all consumer email addresses in Germany (ahead of Gmail). However, United Internet and Deutsche Telekom penalize senders harshly if hard bounce rates exceed 1.5%.
Is KaijuVerifier 100% DSGVO / GDPR compliant for German email lists?
Yes. KaijuVerifier processes email verifications in volatile RAM with zero retention on disk, making it fully compliant with EU GDPR (DSGVO) and Swiss revDSG requirements.