No — comcast.com is IPv4 only.

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

This is a saved measurement from 2026-10-31 00:04 UTC. Check comcast.com live now

IPv6 readiness

The website has no IPv6.

Website over IPv6 comcast.com has no AAAA record.	no
www over IPv6 www.comcast.com has 2 IPv6 addresses and answers on every one we tested. ✓ 2600:1408:c400:f88::20b answers · 443✓ 2600:1408:c400:f86::20b answers · 443	yes
Mail servers (MX) have IPv6 None of the mail servers has an AAAA record. mxa-00143702.gslb.pphosted.com ✗mxb-00143702.gslb.pphosted.com ✗	no
Nameservers have IPv6 5 of 5 nameservers checked have an AAAA record, so IPv6-only resolvers can look the domain up. dns101.comcast.net ✓dns102.comcast.net ✓dns103.comcast.net ✓dns104.comcast.net ✓dns105.comcast.net ✓	yes

What's keeping comcast.com from an A

Give comcast.com 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
Mail servers without IPv6
mxa-00143702.gslb.pphosted.com, mxb-00143702.gslb.pphosted.com have no AAAA record, so mail from IPv6-only servers can't reach them directly. If a provider runs your mail, that's their setting; if you run it, add AAAA records for these hosts.

Check again

comcast.com IPv4 only

A (IPv4)	96.99.227.0
AAAA (IPv6)	none

www.comcast.com Has IPv6

Alias of	www.comcast.com.edgekey.net → e523.dscb.akamaiedge.net
A (IPv4)	104.81.161.16
AAAA (IPv6)	2600:1408:c400:f88::20b 2600:1408:c400:f86::20b

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

IPv6 measurement: comcast.com
Measured 2026-10-31 00:04:33 UTC by aaaa.bot (one server on Fly.io, region iad)

A (IPv4):    96.99.227.0
AAAA (IPv6): none
www AAAA:    2600:1408:c400:f88::20b, 2600:1408:c400:f86::20b

Readiness grade D: The website has no IPv6.
- Website over IPv6: comcast.com has no AAAA record.
- www over IPv6: www.comcast.com has 2 IPv6 addresses and answers on every one we tested.
    2600:1408:c400:f88::20b: answers (TCP 443)
    2600:1408:c400:f86::20b: answers (TCP 443)
- Mail servers (MX) have IPv6: None of the mail servers has an AAAA record.
- Nameservers have IPv6: 5 of 5 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).
No TLS or HTTP request was made.
DNS answers via DNS-over-HTTPS (Cloudflare). Method: https://aaaa.bot/method
Permanent link: https://aaaa.bot/r/blh5DKKNb4

Permanent link: aaaa.bot/r/blh5DKKNb4 · How we measure

Checked 2026-10-31 00:04:33 UTC. Full DNS report: dns.pizza/domain/comcast.com · JSON: /api/v1/comcast.com