Yes — tandfonline.com 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 tandfonline.com has 2 IPv6 addresses and answers on every one we tested. ✓ 2606:4700:4401::ac40:9485 answers · 443✓ 2a06:98c1:310a::6812:277b answers · 443	yes
www over IPv6 www.tandfonline.com has 2 IPv6 addresses and answers on every one we tested. ✓ 2606:4700:4401::ac40:9485 answers · 443✓ 2a06:98c1:310a::6812:277b answers · 443	yes
Mail servers (MX) have IPv6 None of the mail servers has an AAAA record. us-smtp-inbound-1.mimecast.com ✗us-smtp-inbound-2.mimecast.com ✗	no
Nameservers have IPv6 2 of 2 nameservers checked have an AAAA record, so IPv6-only resolvers can look the domain up. lee.ns.cloudflare.com ✓rachel.ns.cloudflare.com ✓	yes

HTTPS over IPv6 · not part of the grade yet
Loads over IPv6 with a valid certificate: HTTP 403.

https://tandfonline.com/ via 2606:4700:4401::ac40:9485 → 403

works

What's keeping tandfonline.com from an A

Mail servers without IPv6
us-smtp-inbound-1.mimecast.com, us-smtp-inbound-2.mimecast.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

tandfonline.com Has IPv6

A (IPv4)	104.18.39.123 172.64.148.133
AAAA (IPv6)	2606:4700:4401::ac40:9485 2a06:98c1:310a::6812:277b

www.tandfonline.com Has IPv6

A (IPv4)	172.64.148.133 104.18.39.123
AAAA (IPv6)	2606:4700:4401::ac40:9485 2a06:98c1:310a::6812:277b

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: tandfonline.com
Measured 2026-10-31 00:04:32 UTC by aaaa.bot (one server on Fly.io, region iad)

A (IPv4):    104.18.39.123, 172.64.148.133
AAAA (IPv6): 2606:4700:4401::ac40:9485, 2a06:98c1:310a::6812:277b
www AAAA:    2606:4700:4401::ac40:9485, 2a06:98c1:310a::6812:277b

Readiness grade B: Works over IPv6, with one gap: its mail servers lack IPv6.
- Website over IPv6: tandfonline.com has 2 IPv6 addresses and answers on every one we tested.
    2606:4700:4401::ac40:9485: answers (TCP 443)
    2a06:98c1:310a::6812:277b: answers (TCP 443)
- www over IPv6: www.tandfonline.com has 2 IPv6 addresses and answers on every one we tested.
    2606:4700:4401::ac40:9485: answers (TCP 443)
    2a06:98c1:310a::6812:277b: 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: HTTP 403.
    https://tandfonline.com/ via 2606:4700:4401::ac40:9485 -> HTTP 403, certificate: valid
DNS answers via DNS-over-HTTPS (Cloudflare). Method: https://aaaa.bot/method
Permanent link: https://aaaa.bot/r/ynIVvSdAor

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

Checked 2026-10-31 00:04:32 UTC — one of the top 1,000 sites, re-checked weekly. Re-check now. Full DNS report: dns.pizza/domain/tandfonline.com · JSON: /api/v1/tandfonline.com