Yes — harnessdump.dev has IPv6.

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

This is a saved measurement from 2026-11-08 19:36 UTC. Check harnessdump.dev live now

IPv6 readiness

Website, mail and DNS all work over IPv6.

Website over IPv6 harnessdump.dev has 2 IPv6 addresses and answers on every one we tested. ✓ 2606:4700:3030::ac43:a58b answers · 443✓ 2606:4700:3036::6815:2ac1 answers · 443	yes
www over IPv6 www.harnessdump.dev has 2 IPv6 addresses and answers on every one we tested. ✓ 2606:4700:3036::6815:2ac1 answers · 443✓ 2606:4700:3030::ac43:a58b 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. beth.ns.cloudflare.com ✓jobs.ns.cloudflare.com ✓	yes

HTTPS over IPv6 · not part of the grade yet
Loads over IPv6 with a valid certificate after 1 redirect: HTTP 200.

https://harnessdump.dev/ via 2606:4700:3030::ac43:a58b → 307https://harnessdump.dev/login via 2606:4700:3030::ac43:a58b → 200

works

Nothing keeping you from an A

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

Check again

harnessdump.dev Has IPv6

A (IPv4)	104.21.42.193 172.67.165.139
AAAA (IPv6)	2606:4700:3030::ac43:a58b 2606:4700:3036::6815:2ac1

www.harnessdump.dev Has IPv6

A (IPv4)	104.21.42.193 172.67.165.139
AAAA (IPv6)	2606:4700:3036::6815:2ac1 2606:4700:3030::ac43:a58b

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: harnessdump.dev
Measured 2026-11-08 19:36:00 UTC by aaaa.bot (one server on Fly.io, region iad)

A (IPv4):    104.21.42.193, 172.67.165.139
AAAA (IPv6): 2606:4700:3030::ac43:a58b, 2606:4700:3036::6815:2ac1
www AAAA:    2606:4700:3036::6815:2ac1, 2606:4700:3030::ac43:a58b

Readiness grade A: Website, mail and DNS all work over IPv6.
- Website over IPv6: harnessdump.dev has 2 IPv6 addresses and answers on every one we tested.
    2606:4700:3030::ac43:a58b: answers (TCP 443)
    2606:4700:3036::6815:2ac1: answers (TCP 443)
- www over IPv6: www.harnessdump.dev has 2 IPv6 addresses and answers on every one we tested.
    2606:4700:3036::6815:2ac1: answers (TCP 443)
    2606:4700:3030::ac43:a58b: 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 after 1 redirect: HTTP 200.
    https://harnessdump.dev/ via 2606:4700:3030::ac43:a58b -> HTTP 307, certificate: valid
    https://harnessdump.dev/login via 2606:4700:3030::ac43:a58b -> HTTP 200, certificate: valid
DNS answers via DNS-over-HTTPS (Cloudflare). Method: https://aaaa.bot/method
Permanent link: https://aaaa.bot/r/yPCANE1-Mb

Permanent link: aaaa.bot/r/yPCANE1-Mb · How we measure

Checked 2026-11-08 19:36:00 UTC. Full DNS report: dns.pizza/domain/harnessdump.dev · Age, certificate and blocklists: how.is/harnessdump.dev · JSON: /api/v1/harnessdump.dev