Yes — darn-toughnz.com has IPv6.

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

IPv6 readiness

Website, mail and DNS all work over IPv6.

Website over IPv6 darn-toughnz.com has 2 IPv6 addresses and answers on every one we tested. ✓ 2606:4700:3037::ac43:a258 answers · 443✓ 2606:4700:3036::6815:f6e answers · 443	yes
www over IPv6 www.darn-toughnz.com has 2 IPv6 addresses and answers on every one we tested. ✓ 2606:4700:3037::ac43:a258 answers · 443✓ 2606:4700:3036::6815:f6e 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. keira.ns.cloudflare.com ✓patryk.ns.cloudflare.com ✓	yes

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

https://darn-toughnz.com/ via 2606:4700:3037::ac43:a258 → 403

works

Nothing keeping you from an A

Nothing to fix
Show it off: add the badge to your README.
[![IPv6](https://aaaa.bot/badge/darn-toughnz.com.svg)](https://aaaa.bot/darn-toughnz.com)

Check again

darn-toughnz.com Has IPv6

A (IPv4)	172.67.162.88 104.21.15.110
AAAA (IPv6)	2606:4700:3037::ac43:a258 2606:4700:3036::6815:f6e

www.darn-toughnz.com Has IPv6

A (IPv4)	104.21.15.110 172.67.162.88
AAAA (IPv6)	2606:4700:3037::ac43:a258 2606:4700:3036::6815:f6e

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: darn-toughnz.com
Measured 2026-10-31 23:02:53 UTC by aaaa.bot (one server on Fly.io, region iad)

A (IPv4):    172.67.162.88, 104.21.15.110
AAAA (IPv6): 2606:4700:3037::ac43:a258, 2606:4700:3036::6815:f6e
www AAAA:    2606:4700:3037::ac43:a258, 2606:4700:3036::6815:f6e

Readiness grade A: Website, mail and DNS all work over IPv6.
- Website over IPv6: darn-toughnz.com has 2 IPv6 addresses and answers on every one we tested.
    2606:4700:3037::ac43:a258: answers (TCP 443)
    2606:4700:3036::6815:f6e: answers (TCP 443)
- www over IPv6: www.darn-toughnz.com has 2 IPv6 addresses and answers on every one we tested.
    2606:4700:3037::ac43:a258: answers (TCP 443)
    2606:4700:3036::6815:f6e: answers (TCP 443)
- Mail servers (MX) have IPv6: No MX records, so mail goes to the domain's own address (implicit MX). It 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://darn-toughnz.com/ via 2606:4700:3037::ac43:a258 -> HTTP 403, certificate: valid
DNS answers via DNS-over-HTTPS (Cloudflare). Method: https://aaaa.bot/method
Permanent link: https://aaaa.bot/r/P-ZEswZgP_

Permanent link: aaaa.bot/r/P-ZEswZgP_ · How we measure

Checked 2026-10-31 23:02:53 UTC. Full DNS report: dns.pizza/domain/darn-toughnz.com · JSON: /api/v1/darn-toughnz.com