Yes — posbill.online has IPv6.

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

IPv6 readiness

Works over IPv6, with one gap: its mail servers lack IPv6.

Website over IPv6 posbill.online has 2 IPv6 addresses and answers on every one we tested. ✓ 2a02:4780:84:a6ac:95a7:6525:cef4:3ad2 answers · 443✓ 2a02:4780:84:e298:de81:cd4d:a558:f79 answers · 443	yes
www over IPv6 www.posbill.online has 2 IPv6 addresses and answers on every one we tested. ✓ 2a02:4780:4b:81af:eb7:1045:36cb:3731 answers · 443✓ 2a02:4780:4c:2871:43e1:939c:e0f0:d0d9 answers · 443	yes
Mail servers (MX) have IPv6 None of the mail servers has an AAAA record. mx2.titan.email ✗mx1.titan.email ✗	no
Nameservers have IPv6 2 of 2 nameservers checked have an AAAA record, so IPv6-only resolvers can look the domain up. artemis.dns-parking.com ✓hermes.dns-parking.com ✓	yes

HTTPS over IPv6 · not part of the grade yet
Loads over IPv6 with a valid certificate after 1 redirect: HTTP 200.

https://posbill.online/ via 2a02:4780:84:a6ac:95a7:6525:cef4:3ad2 → 302https://posbill.online/login.php?error=unauthorized via 2a02:4780:84:a6ac:95a7:6525:cef4:3ad2 → 200

works

What's keeping posbill.online from an A

Mail servers without IPv6
mx2.titan.email, mx1.titan.email have no AAAA record, so mail from IPv6-only servers can't reach them directly. If a provider runs your mail, that's their setting; if you run it, add AAAA records for these hosts.

Check again

posbill.online Has IPv6

A (IPv4)	2.57.91.201 88.222.222.176
AAAA (IPv6)	2a02:4780:84:a6ac:95a7:6525:cef4:3ad2 2a02:4780:84:e298:de81:cd4d:a558:f79

www.posbill.online Has IPv6

Alias of	www.posbill.online.cdn.hstgr.net
A (IPv4)	88.222.222.46 2.57.91.48
AAAA (IPv6)	2a02:4780:4b:81af:eb7:1045:36cb:3731 2a02:4780:4c:2871:43e1:939c:e0f0:d0d9

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

IPv6 measurement: posbill.online
Measured 2026-11-11 21:13:10 UTC by aaaa.bot (one server on Fly.io, region iad)

A (IPv4):    2.57.91.201, 88.222.222.176
AAAA (IPv6): 2a02:4780:84:a6ac:95a7:6525:cef4:3ad2, 2a02:4780:84:e298:de81:cd4d:a558:f79
www AAAA:    2a02:4780:4b:81af:eb7:1045:36cb:3731, 2a02:4780:4c:2871:43e1:939c:e0f0:d0d9

Readiness grade B: Works over IPv6, with one gap: its mail servers lack IPv6.
- Website over IPv6: posbill.online has 2 IPv6 addresses and answers on every one we tested.
    2a02:4780:84:a6ac:95a7:6525:cef4:3ad2: answers (TCP 443)
    2a02:4780:84:e298:de81:cd4d:a558:f79: answers (TCP 443)
- www over IPv6: www.posbill.online has 2 IPv6 addresses and answers on every one we tested.
    2a02:4780:4b:81af:eb7:1045:36cb:3731: answers (TCP 443)
    2a02:4780:4c:2871:43e1:939c:e0f0:d0d9: answers (TCP 443)
- Mail servers (MX) have IPv6: None of the mail servers has an AAAA record.
- Nameservers have IPv6: 2 of 2 nameservers checked have an AAAA record, so IPv6-only resolvers can look the domain up.

Reachability = a TCP connection opened on port 443 (or 80).

HTTPS over IPv6 (not graded): Loads over IPv6 with a valid certificate after 1 redirect: HTTP 200.
    https://posbill.online/ via 2a02:4780:84:a6ac:95a7:6525:cef4:3ad2 -> HTTP 302, certificate: valid
    https://posbill.online/login.php?error=unauthorized via 2a02:4780:84:a6ac:95a7:6525:cef4:3ad2 -> HTTP 200, certificate: valid
DNS answers via DNS-over-HTTPS (Cloudflare). Method: https://aaaa.bot/method
Permanent link: https://aaaa.bot/r/4ma3J_UPbA

Permanent link: aaaa.bot/r/4ma3J_UPbA · How we measure

Checked 2026-11-11 21:13:10 UTC. Full DNS report: dns.pizza/domain/posbill.online · Age, certificate and blocklists: how.is/posbill.online · JSON: /api/v1/posbill.online