B
Post-quantum TLS readiness
1und1.de
Secure today, exposed to harvest-now-decrypt-later
Short answer
No. As of 2026-11-03, 1und1.de does not negotiate post-quantum key exchange; it uses x25519 over TLSv1.3 (Quantum Aether grade B), so recorded traffic is exposed to harvest-now-decrypt-later.
| Grade | B |
|---|---|
| Key exchange | x25519 |
| Post-quantum | no (classical) |
| TLS | TLSv1.3 |
| Hosting network | IONOS SE |
| Tranco rank | #4201 |
| Country | 🇩🇪 Germany: #14/26 (52.0%) |
From our weekly tracker of the top 10,000 sites, scanned on 2026-11-03 · /adoption
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