Yes — fda.gov has IPv6.

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

IPv6 readiness

Website, mail and DNS all work over IPv6.

Website over IPv6 fda.gov has 2 IPv6 addresses and answers on every one we tested. ✓ 2600:1408:5400:35::17ca:e6cc answers · 443✓ 2600:1408:5400:35::17ca:e6ce answers · 443	yes
www over IPv6 www.fda.gov has 2 IPv6 addresses and answers on every one we tested. ✓ 2600:1408:5400:35::17ca:e6ce answers · 443✓ 2600:1408:5400:35::17ca:e6cc answers · 443	yes
Mail servers (MX) have IPv6 Every mail server has an AAAA record. smtp6.fda.gov ✓smtp7.fda.gov ✓smtp8.fda.gov ✓smtp9.fda.gov ✓	yes
Nameservers have IPv6 6 of 6 nameservers checked have an AAAA record, so IPv6-only resolvers can look the domain up. a2-65.akam.net ✓a7-67.akam.net ✓a1-242.akam.net ✓a13-64.akam.net ✓a20-65.akam.net ✓a24-66.akam.net ✓	yes

HTTPS over IPv6 · not part of the grade yet
Loads over IPv6 with a valid certificate after 2 redirects: HTTP 404.

https://fda.gov/ via 2600:1408:5400:35::17ca:e6cc → 302https://fda.gov/apology_objects/abuse-detection-apology.html via 2600:1408:5400:35::17ca:e6cc → 301https://www.fda.gov/apology_objects/abuse-detection-apology.html via 2600:1408:5400:35::17ca:e6ce → 404

works

Nothing keeping you from an A

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

Check again

fda.gov Has IPv6

A (IPv4)	23.212.251.4 23.212.251.15
AAAA (IPv6)	2600:1408:5400:35::17ca:e6cc 2600:1408:5400:35::17ca:e6ce

www.fda.gov Has IPv6

Alias of	prod-resolver-www-sni.fda.gov.akadns.net → www-sni.fda.gov.edgekey.net → e302277.dscb.akamaiedge.net
A (IPv4)	23.205.106.89 23.205.106.88
AAAA (IPv6)	2600:1408:5400:35::17ca:e6ce 2600:1408:5400:35::17ca:e6cc

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: fda.gov
Measured 2026-10-31 03:04:31 UTC by aaaa.bot (one server on Fly.io, region iad)

A (IPv4):    23.212.251.4, 23.212.251.15
AAAA (IPv6): 2600:1408:5400:35::17ca:e6cc, 2600:1408:5400:35::17ca:e6ce
www AAAA:    2600:1408:5400:35::17ca:e6ce, 2600:1408:5400:35::17ca:e6cc

Readiness grade A: Website, mail and DNS all work over IPv6.
- Website over IPv6: fda.gov has 2 IPv6 addresses and answers on every one we tested.
    2600:1408:5400:35::17ca:e6cc: answers (TCP 443)
    2600:1408:5400:35::17ca:e6ce: answers (TCP 443)
- www over IPv6: www.fda.gov has 2 IPv6 addresses and answers on every one we tested.
    2600:1408:5400:35::17ca:e6ce: answers (TCP 443)
    2600:1408:5400:35::17ca:e6cc: answers (TCP 443)
- Mail servers (MX) have IPv6: Every mail server has an AAAA record.
- Nameservers have IPv6: 6 of 6 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 2 redirects: HTTP 404.
    https://fda.gov/ via 2600:1408:5400:35::17ca:e6cc -> HTTP 302, certificate: valid
    https://fda.gov/apology_objects/abuse-detection-apology.html via 2600:1408:5400:35::17ca:e6cc -> HTTP 301, certificate: valid
    https://www.fda.gov/apology_objects/abuse-detection-apology.html via 2600:1408:5400:35::17ca:e6ce -> HTTP 404, certificate: valid
DNS answers via DNS-over-HTTPS (Cloudflare). Method: https://aaaa.bot/method
Permanent link: https://aaaa.bot/r/nx1yjmfYFH

Permanent link: aaaa.bot/r/nx1yjmfYFH · How we measure

Checked 2026-10-31 03:04:31 UTC — one of the top 1,000 sites, re-checked weekly. Re-check now. Full DNS report: dns.pizza/domain/fda.gov · JSON: /api/v1/fda.gov