Yes — usql.online has IPv6.

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

IPv6 readiness

Website, mail and DNS all work over IPv6.

Website over IPv6 usql.online has 2 IPv6 addresses and answers on every one we tested. ✓ 2606:4700:3033::6815:19d7 answers · 443✓ 2606:4700:3035::ac43:86bc answers · 443	yes
www over IPv6 www.usql.online has 2 IPv6 addresses and answers on every one we tested. ✓ 2606:4700:3033::6815:19d7 answers · 443✓ 2606:4700:3035::ac43:86bc 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. leo.ns.cloudflare.com ✓sky.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://usql.online/ via 2606:4700:3033::6815:19d7 → 302https://www.google.com/ via 2001:4860:482b:7700:: → 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/usql.online.svg)](https://aaaa.bot/usql.online)

Check again

usql.online Has IPv6

A (IPv4)	172.67.134.188 104.21.25.215
AAAA (IPv6)	2606:4700:3033::6815:19d7 2606:4700:3035::ac43:86bc

www.usql.online Has IPv6

A (IPv4)	172.67.134.188 104.21.25.215
AAAA (IPv6)	2606:4700:3033::6815:19d7 2606:4700:3035::ac43:86bc

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: usql.online
Measured 2026-11-05 12:32:30 UTC by aaaa.bot (one server on Fly.io, region iad)

A (IPv4):    172.67.134.188, 104.21.25.215
AAAA (IPv6): 2606:4700:3033::6815:19d7, 2606:4700:3035::ac43:86bc
www AAAA:    2606:4700:3033::6815:19d7, 2606:4700:3035::ac43:86bc

Readiness grade A: Website, mail and DNS all work over IPv6.
- Website over IPv6: usql.online has 2 IPv6 addresses and answers on every one we tested.
    2606:4700:3033::6815:19d7: answers (TCP 443)
    2606:4700:3035::ac43:86bc: answers (TCP 443)
- www over IPv6: www.usql.online has 2 IPv6 addresses and answers on every one we tested.
    2606:4700:3033::6815:19d7: answers (TCP 443)
    2606:4700:3035::ac43:86bc: 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://usql.online/ via 2606:4700:3033::6815:19d7 -> HTTP 302, certificate: valid
    https://www.google.com/ via 2001:4860:482b:7700:: -> HTTP 200, certificate: valid
DNS answers via DNS-over-HTTPS (Cloudflare). Method: https://aaaa.bot/method
Permanent link: https://aaaa.bot/r/Eup0c9Gmrn

Permanent link: aaaa.bot/r/Eup0c9Gmrn · How we measure

Checked 2026-11-05 12:32:30 UTC. Full DNS report: dns.pizza/domain/usql.online · Age, certificate and blocklists: how.is/usql.online · JSON: /api/v1/usql.online