Yes — tantula.com has IPv6.

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

IPv6 readiness

Website, mail and DNS all work over IPv6.

Website over IPv6 tantula.com has 2 IPv6 addresses and answers on every one we tested. ✓ 2606:4700:3033::6815:cf3 answers · 443✓ 2606:4700:3032::ac43:99f2 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. derek.ns.cloudflare.com ✓paris.ns.cloudflare.com ✓	yes

HTTPS over IPv6 · not part of the grade yet
Loads over IPv6 with a valid certificate after 1 redirect: HTTP 200.

https://tantula.com/ via 2606:4700:3033::6815:cf3 → 302https://red-bonus-1210.cloudflareaccess.com/cdn-cgi/access/login/tantula.com?kid=e54ec399a98fe466af91e15a95f4d263ec676bbff7d12fdf83729266b9408fa8&meta=eyJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiIsImtpZCI6Ijg2OGFmMjMzMzMwYTk2ZmFjNTUzMTBhMmQyN2E2MmQ1ZWM1YWY5Zjg3ZDBhOTg5OTNhMzk0MjZlMDg1NGI2NzcifQ.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.omtNUufQ8422vJp8V4CF9_sqH7_8tcEEL6JJ-70VVip_-Dd36D6hlBAcjTz13wsHDXNDv0wxfxXeaM7p8v8bDkbQ9NxuHX1twVNgjGOqu4Rq9nRcaQxr9LC9QCq7WyvGDJ4Vj3BU6fN4jIx_g0LDabAcEJfNfr_OIHn9GjVFlkSOVcnzsvBWFYN5esRLZ20JAA2llgn7ZNKucEfEDh5YgMEZxsFjwCdJoksx2WWd8dwespltYhu34f_d_Yq3HHCkR1kMFGU0swHf3xt79Ai1eXe2R2w1ikbfHlzxPmkIIzT5TaJpfnnPI7mNJR2VixuEaYr1yVU8qkgNn0IG_R3aHQ&redirect_url=%2F via 2606:4700:300a::6813:c31d → 200

works

Nothing keeping you from an A

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

Check again

tantula.com Has IPv6

A (IPv4)	104.21.12.243 172.67.153.242
AAAA (IPv6)	2606:4700:3033::6815:cf3 2606:4700:3032::ac43:99f2

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: tantula.com
Measured 2026-11-11 08:33:36 UTC by aaaa.bot (one server on Fly.io, region iad)

A (IPv4):    104.21.12.243, 172.67.153.242
AAAA (IPv6): 2606:4700:3033::6815:cf3, 2606:4700:3032::ac43:99f2

Readiness grade A: Website, mail and DNS all work over IPv6.
- Website over IPv6: tantula.com has 2 IPv6 addresses and answers on every one we tested.
    2606:4700:3033::6815:cf3: answers (TCP 443)
    2606:4700:3032::ac43:99f2: answers (TCP 443)
- 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: 2 of 2 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 1 redirect: HTTP 200.
    https://tantula.com/ via 2606:4700:3033::6815:cf3 -> HTTP 302, certificate: valid
    https://red-bonus-1210.cloudflareaccess.com/cdn-cgi/access/login/tantula.com?kid=e54ec399a98fe466af91e15a95f4d263ec676bbff7d12fdf83729266b9408fa8&meta=eyJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiIsImtpZCI6Ijg2OGFmMjMzMzMwYTk2ZmFjNTUzMTBhMmQyN2E2MmQ1ZWM1YWY5Zjg3ZDBhOTg5OTNhMzk0MjZlMDg1NGI2NzcifQ.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.omtNUufQ8422vJp8V4CF9_sqH7_8tcEEL6JJ-70VVip_-Dd36D6hlBAcjTz13wsHDXNDv0wxfxXeaM7p8v8bDkbQ9NxuHX1twVNgjGOqu4Rq9nRcaQxr9LC9QCq7WyvGDJ4Vj3BU6fN4jIx_g0LDabAcEJfNfr_OIHn9GjVFlkSOVcnzsvBWFYN5esRLZ20JAA2llgn7ZNKucEfEDh5YgMEZxsFjwCdJoksx2WWd8dwespltYhu34f_d_Yq3HHCkR1kMFGU0swHf3xt79Ai1eXe2R2w1ikbfHlzxPmkIIzT5TaJpfnnPI7mNJR2VixuEaYr1yVU8qkgNn0IG_R3aHQ&redirect_url=%2F via 2606:4700:300a::6813:c31d -> HTTP 200, certificate: valid
DNS answers via DNS-over-HTTPS (Cloudflare). Method: https://aaaa.bot/method
Permanent link: https://aaaa.bot/r/D7qukggdzI

Permanent link: aaaa.bot/r/D7qukggdzI · How we measure

Checked 2026-11-11 08:33:36 UTC. Full DNS report: dns.pizza/domain/tantula.com · Age, certificate and blocklists: how.is/tantula.com · JSON: /api/v1/tantula.com