Verified Answer - gmx.com / gmx.net / gmx.de / web.de

Is GMX a Catch-All Domain?

No - GMX is not a catch-all domain.

GMX (gmx.com, gmx.net, gmx.de) and its sister brand Web.de both run on United Internet's shared infrastructure and reject SMTP connections to non-existent addresses. Both are individually verifiable. BounceZero handles all GMX and Web.de domains through its dedicated German ISP verification path.

Verify GMX Addresses Free

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GMX, Web.de, Freenet - United Internet Infrastructure

GMX and Web.de are the two largest German freemail providers and share United Internet's MX infrastructure. All domains across both brands are verifiable individually - none are catch-all by default.

gmx.com

gmx.net

gmx.de

gmx.at

gmx.ch

web.de

Why GMX Lists Have High Bounce Rates

GMX and Web.de accounts accumulate in German email lists because they were extremely popular in the 2000s and early 2010s. Many users have since migrated to Gmail or T-Online. Old GMX accounts get deactivated after prolonged inactivity - causing hard bounces on lists that haven't been verified recently. BounceZero's live SMTP check catches these deactivated accounts before they affect your sender score.

Frequently Asked Questions

Is GMX a catch-all domain?

No. GMX (gmx.com, gmx.net, gmx.de) and Web.de reject SMTP connections to non-existent addresses. All GMX domains are individually verifiable.

Does GMX share infrastructure with Web.de?

Yes - GMX and Web.de are both owned by United Internet and share the same mail servers. BounceZero handles both through its German ISP verification path.

Why do GMX addresses bounce?

Not catch-all - list decay. Old GMX accounts get deactivated after inactivity. German lists with addresses from 2010-2015 often have significant bounce rates from abandoned GMX accounts. Verify before sending.

How much does it cost?

$3 per 1,000 verifications. 100 free credits on signup - no credit card required.

Verify GMX and Web.de Addresses Before You Send.

German ISP-optimised path. 100 free credits to start.

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Is [provider] a catch-all domain?

Per-provider answers - SMTP behaviour, detection methods, and how BounceZero handles each

Is Gmail catch-all?

No - returns 550 for unknown addresses

Is Outlook catch-all?

No - but blocks verifier IPs (Microsoft PTR policy)

Is Yahoo catch-all?

No - but throttles SMTP probes heavily

Is Hotmail catch-all?

No - runs on same Microsoft infra as Outlook

Is iCloud catch-all?

No - icloud.com/me.com/mac.com all individually verifiable

Is ProtonMail catch-all?

Not by design - but SMTP gateway returns 250 for all

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