Yes — santanu.bio has IPv6.

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

Measured 2026-11-03 10:11 UTC. We reuse a result for up to a week, so we aren't testing the same site over and over. Check santanu.bio now

B
IPv6 readiness
Works over IPv6, with one gap: its mail servers lack IPv6.
Website over IPv6
santanu.bio has an AAAA record and answers on it.
✓ 2607:f1c0:100f:f000::200 answers · 443
yes
www over IPv6
www.santanu.bio has an AAAA record and answers on it.
✓ 2607:f1c0:100f:f000::200 answers · 443
yes
Mail servers (MX) have IPv6
None of the mail servers has an AAAA record.
mx01.ionos.com ✗mx00.ionos.com ✗
no
Nameservers have IPv6
4 of 4 nameservers checked have an AAAA record, so IPv6-only resolvers can look the domain up.
ns1068.ui-dns.org ✓ns1085.ui-dns.com ✓ns1032.ui-dns.de ✓ns1117.ui-dns.biz ✓
yes

First measured 2026-11-03; last confirmed 2026-11-03.

HTTPS over IPv6 · not part of the grade yet
Loads over IPv6 with a valid certificate: HTTP 200.
https://santanu.bio/ via 2607:f1c0:100f:f000::200 → 200
works
 Load santanu.bio over IPv6 from up to six other places — a second opinion.

What's keeping santanu.bio from an A

  1. Mail servers without IPv6
    mx01.ionos.com, mx00.ionos.com 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

santanu.bio  Has IPv6

A (IPv4)74.208.236.208
AAAA (IPv6)2607:f1c0:100f:f000::200

www.santanu.bio  Has IPv6

A (IPv4)74.208.236.208
AAAA (IPv6)2607:f1c0:100f:f000::200

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/ONPOvftwSA · How we measure

Checked 2026-11-03 10:11:26 UTC. Full DNS report: dns.pizza/domain/santanu.bio · Age, certificate and blocklists: how.is/santanu.bio · JSON: /api/v1/santanu.bio