No — eff.org is IPv4 only.

Has an IPv4 address but no IPv6 (AAAA) record. IPv6-only visitors can't reach it directly.

D
IPv6 readiness
The website has no IPv6.
Website over IPv6
eff.org has no AAAA record.		no
www over IPv6
www.eff.org has 4 IPv6 addresses and answers on every one we tested.
✓ 2a04:4e42::201 answers · 443✓ 2a04:4e42:200::201 answers · 443✓ 2a04:4e42:400::201 answers · 443✓ 2a04:4e42:600::201 answers · 443
yes
Mail servers (MX) have IPv6
Every mail server has an AAAA record.
eff-org.mail.protection.outlook.com ✓
yes
Nameservers have IPv6
No nameserver has an AAAA record — an IPv6-only resolver can't reach this domain's DNS.
ns4.eff.org ✗ns2.eff.org ✗ns1.eff.org ✗
no

What's keeping eff.org from an A

  1. Give eff.org an IPv6 address
    Ask your hosting provider for the site's IPv6 address (or the hostname to point at), then publish it as an AAAA record. If your host doesn't offer IPv6, a proxy that does can sit in front. How to add an AAAA record
  2. Nameservers without IPv6
    ns4.eff.org, ns2.eff.org, ns1.eff.org all have no AAAA record, so a resolver that only speaks IPv6 can't look your domain up. Most DNS providers offer IPv6 nameservers; ask yours, or move DNS to one that does.

Check again

eff.org  IPv4 only

A (IPv4)173.239.79.200
AAAA (IPv6)none

www.eff.org  Has IPv6

Alias ofeff.map.fastly.net
A (IPv4)151.101.64.201
151.101.128.201
151.101.192.201
151.101.0.201
AAAA (IPv6)2a04:4e42::201
2a04:4e42:200::201
2a04:4e42:400::201
2a04:4e42:600::201

What this means

Visitors on IPv6-only networks (many mobile carriers) can still reach it, but only through a translator their carrier runs (NAT64). The site itself has no IPv6 address — and you can't make one up from the IPv4. Why some hosts don't offer it

Copy the evidence — a citation-ready record of this measurement

 Permanent link: aaaa.bot/r/zVXf0wX8Fn · How we measure

Checked 2026-10-31 05:34:28 UTC. Full DNS report: dns.pizza/domain/eff.org · JSON: /api/v1/eff.org