Yes — ftp.census.gov has IPv6.

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

A
IPv6 readiness
Website, mail and DNS all work over IPv6.
Website over IPv6
ftp.census.gov has an AAAA record and answers on it.
✓ 2610:20:2010:a09:1000:0:9481:4b23 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.
ns1e.census.gov ✓ns2e.census.gov ✓
yes
HTTPS over IPv6 · not part of the grade yet
Loads over IPv6 with a valid certificate after 1 redirect: HTTP 200.
https://ftp.census.gov/ via 2610:20:2010:a09:1000:0:9481:4b23 → 302https://www2.census.gov/ via 2606:4700:78::90:0:181 → 200
works
 Load ftp.census.gov over IPv6 from up to six other places — a second opinion.

Nothing keeping you from an A

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

Check again

ftp.census.gov  Has IPv6

A (IPv4)148.129.75.35
AAAA (IPv6)2610:20:2010:a09:1000:0:9481:4b23

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

 Permanent link: aaaa.bot/r/cSF4r4I5Pb · How we measure

Checked 2026-11-01 22:16:52 UTC. Full DNS report: dns.pizza/domain/ftp.census.gov · JSON: /api/v1/ftp.census.gov