Yes — autodiscover.mastercard.com has IPv6.

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

IPv6 readiness

Website, mail and DNS all work over IPv6.

Website over IPv6 autodiscover.mastercard.com has 4 IPv6 addresses and answers on every one we tested (4 more not tested). ✓ 2603:1036:207:455::8 answers · 80✓ 2603:1036:207:2001::8 answers · 80✓ 2603:1036:302:415d::8 answers · 80✓ 2603:1036:302:415e::8 answers · 80– 2603:1036:302:4832::8 not tested– 2603:1036:302:4836::8 not tested– 2603:1036:302:4844::8 not tested– 2603:1036:302:5061::8 not tested	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 6 of 6 nameservers checked have an AAAA record, so IPv6-only resolvers can look the domain up. a9-64.akam.net ✓a1-29.akam.net ✓a7-67.akam.net ✓a18-64.akam.net ✓a22-65.akam.net ✓a26-66.akam.net ✓	yes

HTTPS over IPv6 · not part of the grade yet
autodiscover.mastercard.com didn't complete an HTTPS request over IPv6 (ECONNREFUSED).

https://autodiscover.mastercard.com/ via 2603:1036:207:455::8 · ECONNREFUSED

Nothing keeping you from an A

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

Check again

autodiscover.mastercard.com Has IPv6

Alias of	autodiscover.outlook.com → autodiscover.outlook.cloud.microsoft → acdcatm.autodiscover.mira.tm.svc.cloud.microsoft → atm.autodiscover.mira.tm.svc.cloud.microsoft
A (IPv4)	40.104.46.8 40.104.46.72 52.96.87.216 52.96.109.216 52.96.109.248 52.96.111.8 52.96.230.168 52.96.242.24
AAAA (IPv6)	2603:1036:207:455::8 2603:1036:207:2001::8 2603:1036:302:415d::8 2603:1036:302:415e::8 2603:1036:302:4832::8 2603:1036:302:4836::8 2603:1036:302:4844::8 2603:1036:302:5061::8

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: autodiscover.mastercard.com
Measured 2026-11-02 13:36:09 UTC by aaaa.bot (one server on Fly.io, region iad)

A (IPv4):    40.104.46.8, 40.104.46.72, 52.96.87.216, 52.96.109.216, 52.96.109.248, 52.96.111.8, 52.96.230.168, 52.96.242.24
AAAA (IPv6): 2603:1036:207:455::8, 2603:1036:207:2001::8, 2603:1036:302:415d::8, 2603:1036:302:415e::8, 2603:1036:302:4832::8, 2603:1036:302:4836::8, 2603:1036:302:4844::8, 2603:1036:302:5061::8

Readiness grade A: Website, mail and DNS all work over IPv6.
- Website over IPv6: autodiscover.mastercard.com has 4 IPv6 addresses and answers on every one we tested (4 more not tested).
    2603:1036:207:455::8: answers (TCP 80)
    2603:1036:207:2001::8: answers (TCP 80)
    2603:1036:302:415d::8: answers (TCP 80)
    2603:1036:302:415e::8: answers (TCP 80)
    2603:1036:302:4832::8: not tested
    2603:1036:302:4836::8: not tested
    2603:1036:302:4844::8: not tested
    2603:1036:302:5061::8: not tested
- 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: 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): autodiscover.mastercard.com didn't complete an HTTPS request over IPv6 (ECONNREFUSED).
    https://autodiscover.mastercard.com/ via 2603:1036:207:455::8 (ECONNREFUSED)
DNS answers via DNS-over-HTTPS (Cloudflare). Method: https://aaaa.bot/method
Permanent link: https://aaaa.bot/r/kLxLNaUYYB

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

Checked 2026-11-02 13:36:09 UTC. Full DNS report: dns.pizza/domain/autodiscover.mastercard.com · JSON: /api/v1/autodiscover.mastercard.com