Yes — duefox.app has IPv6.

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

IPv6 readiness

Website, mail and DNS all work over IPv6.

Website over IPv6 duefox.app has 2 IPv6 addresses and answers on every one we tested. ✓ 2606:4700:3032::6815:172b answers · 443✓ 2606:4700:3035::ac43:d0d1 answers · 443	yes
www over IPv6 www.duefox.app has 2 IPv6 addresses and answers on every one we tested. ✓ 2606:4700:3035::ac43:d0d1 answers · 443✓ 2606:4700:3032::6815:172b 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. joel.ns.cloudflare.com ✓wren.ns.cloudflare.com ✓	yes

HTTPS over IPv6 · not part of the grade yet
Redirects to apps.shopify.com, which has no IPv6 address — so IPv6 visitors end up needing IPv4 after all.

https://duefox.app/ via 2606:4700:3032::6815:172b → 302https://apps.shopify.com/wholesale-terms · redirects to apps.shopify.com, which has no IPv6 address

problem

Nothing keeping you from an A

A redirect leads off IPv6
Redirects to apps.shopify.com, which has no IPv6 address — so IPv6 visitors end up needing IPv4 after all. Give the redirect target IPv6 too, or redirect somewhere that has it.

Check again

duefox.app Has IPv6

A (IPv4)	172.67.208.209 104.21.23.43
AAAA (IPv6)	2606:4700:3032::6815:172b 2606:4700:3035::ac43:d0d1

www.duefox.app Has IPv6

A (IPv4)	172.67.208.209 104.21.23.43
AAAA (IPv6)	2606:4700:3035::ac43:d0d1 2606:4700:3032::6815:172b

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: duefox.app
Measured 2026-11-11 07:42:30 UTC by aaaa.bot (one server on Fly.io, region iad)

A (IPv4):    172.67.208.209, 104.21.23.43
AAAA (IPv6): 2606:4700:3032::6815:172b, 2606:4700:3035::ac43:d0d1
www AAAA:    2606:4700:3035::ac43:d0d1, 2606:4700:3032::6815:172b

Readiness grade A: Website, mail and DNS all work over IPv6.
- Website over IPv6: duefox.app has 2 IPv6 addresses and answers on every one we tested.
    2606:4700:3032::6815:172b: answers (TCP 443)
    2606:4700:3035::ac43:d0d1: answers (TCP 443)
- www over IPv6: www.duefox.app has 2 IPv6 addresses and answers on every one we tested.
    2606:4700:3035::ac43:d0d1: answers (TCP 443)
    2606:4700:3032::6815:172b: 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): Redirects to apps.shopify.com, which has no IPv6 address — so IPv6 visitors end up needing IPv4 after all.
    https://duefox.app/ via 2606:4700:3032::6815:172b -> HTTP 302, certificate: valid
    https://apps.shopify.com/wholesale-terms (redirects to apps.shopify.com, which has no IPv6 address)
DNS answers via DNS-over-HTTPS (Cloudflare). Method: https://aaaa.bot/method
Permanent link: https://aaaa.bot/r/wlseQKipVX

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

Checked 2026-11-11 07:42:30 UTC. Full DNS report: dns.pizza/domain/duefox.app · Age, certificate and blocklists: how.is/duefox.app · JSON: /api/v1/duefox.app