Has both IPv4 (A) and IPv6 (AAAA) addresses.
| Website over IPv6 harvardcollectionservices.com has 2 IPv6 addresses and answers on every one we tested. ✓ 2606:4700:3034::ac43:831d answers · 443✓ 2606:4700:3031::6815:3bf answers · 443 | yes |
| www over IPv6 www.harvardcollectionservices.com has 2 IPv6 addresses and answers on every one we tested. ✓ 2606:4700:3031::6815:3bf answers · 443✓ 2606:4700:3034::ac43:831d answers · 443 | yes |
| Mail servers (MX) have IPv6 Every mail server has an AAAA record. route1.mx.cloudflare.net ✓route3.mx.cloudflare.net ✓route2.mx.cloudflare.net ✓ | yes |
| Nameservers have IPv6 2 of 2 nameservers checked have an AAAA record, so IPv6-only resolvers can look the domain up. emely.ns.cloudflare.com ✓seth.ns.cloudflare.com ✓ | yes |
| HTTPS over IPv6 · not part of the grade yet Loads over IPv6 with a valid certificate: HTTP 200. https://harvardcollectionservices.com/ via 2606:4700:3034::ac43:831d → 200 | works |
harvardcollectionservices.com Has IPv6
| A (IPv4) | 104.21.3.191 172.67.131.29 |
|---|---|
| AAAA (IPv6) | 2606:4700:3034::ac43:831d 2606:4700:3031::6815:3bf |
www.harvardcollectionservices.com Has IPv6
| A (IPv4) | 172.67.131.29 104.21.3.191 |
|---|---|
| AAAA (IPv6) | 2606:4700:3031::6815:3bf 2606:4700:3034::ac43:831d |
Browsers on dual-stack networks will usually pick IPv6 here (the "Happy Eyeballs" algorithm races both and prefers v6).
Permanent link: aaaa.bot/r/FA6fuUyHRD · How we measure
Checked 2026-11-05 18:43:37 UTC. Full DNS report: dns.pizza/domain/harvardcollectionservices.com · Age, certificate and blocklists: how.is/harvardcollectionservices.com · JSON: /api/v1/harvardcollectionservices.com