Yes — login.firmy.cz has IPv6.

Has both IPv4 (A) and IPv6 (AAAA) addresses.

A
IPv6 readiness
Website, mail and DNS all work over IPv6.
Website over IPv6
login.firmy.cz has an AAAA record and answers on it.
✓ 2a02:598:a::78:104 answers · 443
yes
Mail servers (MX) have IPv6
No MX records, so mail goes to the domain's own address (implicit MX). It has an AAAA record.		yes
Nameservers have IPv6
2 of 2 nameservers checked have an AAAA record, so IPv6-only resolvers can look the domain up.
ams.seznam.cz ✓ans.seznam.cz ✓
yes
HTTPS over IPv6 · not part of the grade yet
Loads over IPv6 with a valid certificate: HTTP 200.
https://login.firmy.cz/ via 2a02:598:a::78:104 → 200
works
 Which outside scripts, fonts, payments or chat login.firmy.cz loads from have no IPv6.
 Load login.firmy.cz over IPv6 from up to six other places — a second opinion.

Nothing keeping you from an A

  1. Nothing to fix
    Show it off: add the badge to your README.
    [![IPv6](https://aaaa.bot/badge/login.firmy.cz.svg)](https://aaaa.bot/login.firmy.cz)

Check again

login.firmy.cz  Has IPv6

Alias oflogin.szn.cz
A (IPv4)77.75.78.104
AAAA (IPv6)2a02:598:a::78:104

Browsers on dual-stack networks will usually pick IPv6 here (the "Happy Eyeballs" algorithm races both and prefers v6).

Copy the evidence — a citation-ready record of this measurement

 Permanent link: aaaa.bot/r/nDnHUNHsTC · How we measure

Checked 2026-11-15 18:18:43 UTC. Full DNS report: dns.pizza/domain/login.firmy.cz · Age, certificate and blocklists: how.is/login.firmy.cz · JSON: /api/v1/login.firmy.cz