`51classes.com`

DNSSEC	⚠️ Not signed
A	2606:4700:3033::6815:4ec9^{🇺🇸 Cloudflare2606:4700:3033::/48 , Inc. 101 Townsend Street, San Francisco, California 94107, US} ✓ In HTTPS hints
A	2606:4700:3037::ac43:8970^{🇺🇸 Cloudflare2606:4700:3037::/48 , Inc. 101 Townsend Street, San Francisco, California 94107, US} ✓ In HTTPS hints
A	104.21.78.201^{Cloudflare104.21.64.0/20 , Inc. 101 Townsend Street, San Francisco, California 94107, US} ✓ In HTTPS hints
A	172.67.137.112^{🇺🇸 Cloudflare172.67.128.0/20 , Inc. 101 Townsend Street, San Francisco, California 94107, US} ✓ In HTTPS hints
NS	`brenna.ns.cloudflare.com` ⭐
		A	2606:4700:50::a29f:26b0^{🇺🇸 Cloudflare2606:4700:50::/44 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`brenna.ns.cloudflare.com`
		A	2803:f800:50::6ca2:c2b0^{🇨🇷 Cloudflare2803:f800:50::/45 LACNIC generated route6 for CloudFlare Latin America S.R.L}
			PTR	`brenna.ns.cloudflare.com`
		A	2a06:98c1:50::ac40:22b0^{🇺🇸 Cloudflare2a06:98c1:50::/45}
			PTR	`brenna.ns.cloudflare.com`
		A	108.162.194.176^{🇺🇸 Cloudflare108.162.194.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`brenna.ns.cloudflare.com`
		A	162.159.38.176^{Cloudflare162.159.32.0/20 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`brenna.ns.cloudflare.com`
		A	172.64.34.176^{🇺🇸 Cloudflare172.64.34.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`brenna.ns.cloudflare.com`
NS	`toby.ns.cloudflare.com`
		A	2606:4700:58::adf5:3bef^{🇺🇸 Cloudflare2606:4700:50::/44 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`toby.ns.cloudflare.com`
		A	2803:f800:50::6ca2:c1ef^{🇨🇷 Cloudflare2803:f800:50::/45 LACNIC generated route6 for CloudFlare Latin America S.R.L}
			PTR	`toby.ns.cloudflare.com`
		A	2a06:98c1:50::ac40:21ef^{🇺🇸 Cloudflare2a06:98c1:50::/45}
			PTR	`toby.ns.cloudflare.com`
		A	108.162.193.239^{🇺🇸 Cloudflare108.162.193.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`toby.ns.cloudflare.com`
		A	172.64.33.239^{🇺🇸 Cloudflare172.64.33.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`toby.ns.cloudflare.com`
		A	173.245.59.239^{🇺🇸 Cloudflare173.245.59.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`toby.ns.cloudflare.com`
HTTPS	HTTP/3, HTTP/2 ✓ hints match
		IPv4 hints	104.21.78.201, 172.67.137.112
		IPv6 hints	2606:4700:3033::6815:4ec9, 2606:4700:3037::ac43:8970
		ECH	X25519, HKDF-SHA256 + AES-128-GCM draft, id=125, name=cloudflare-ech.com
SOA	`brenna.ns.cloudflare.com`dns@cloudflare.com serial=2401802632

`com`

	DNSSEC	🔒 Signed (DS record present)
	NS	`a.gtld-servers.net` ⭐
	NS	`b.gtld-servers.net`
	NS	`c.gtld-servers.net`
	NS	`d.gtld-servers.net`
	NS	`e.gtld-servers.net`
	NS	`f.gtld-servers.net`
	NS	`g.gtld-servers.net`
	NS	`h.gtld-servers.net`
	NS	`i.gtld-servers.net`
	NS	`j.gtld-servers.net`
	NS	`k.gtld-servers.net`
	NS	`l.gtld-servers.net`
	NS	`m.gtld-servers.net`
	SOA	`a.gtld-servers.net`nstld@verisign-grs.com serial=1778491122

Same first word

51classes.com

DNS History

22 records (6 active, 16 former)

○NSa.share-dns.com2026-04-12 → 2026-04-12 · 3 obs

○ 2016-09-09 08:26:20
● 2026-04-12 05:59:10
○ 2026-05-11 09:30:16

○NSa11.share-dns.com2026-04-12 → 2026-04-12 · 3 obs

○ 2016-09-09 08:26:20
● 2026-04-12 05:59:10
○ 2026-05-11 09:30:16

○NSb.share-dns.net2026-04-12 → 2026-04-12 · 3 obs

○ 2016-09-09 08:26:20
● 2026-04-12 05:59:10
○ 2026-05-11 09:30:16

○NSb11.share-dns.net2026-04-12 → 2026-04-12 · 3 obs

○ 2016-09-09 08:26:20
● 2026-04-12 05:59:10
○ 2026-05-11 09:30:16

●NSbrenna.ns.cloudflare.com2026-05-11 → 2026-05-11 · 2 obs

○ 2026-04-12 05:59:10
● 2026-05-11 09:30:16

○NSns1.51dns.com2015-07-26 → 2015-12-06 · 4 obs

● 2015-07-26 01:47:48
● 2015-12-06 00:20:08
○ 2016-03-28 08:57:50
○ 2026-05-11 09:30:16

○NSns2.51dns.com2015-07-26 → 2015-12-06 · 4 obs

● 2015-07-26 01:47:48
● 2015-12-06 00:20:08
○ 2016-03-28 08:57:50
○ 2026-05-11 09:30:16

○NSns37.domaincontrol.com2016-03-28 → 2016-03-28 · 4 obs

○ 2015-12-06 00:20:08
● 2016-03-28 08:57:50
○ 2016-09-09 08:26:20
○ 2026-05-11 09:30:16

○NSns38.domaincontrol.com2016-03-28 → 2016-03-28 · 4 obs

○ 2015-12-06 00:20:08
● 2016-03-28 08:57:50
○ 2016-09-09 08:26:20
○ 2026-05-11 09:30:16

○NSns5.dnsdun.com2016-09-09 → 2016-09-09 · 4 obs

○ 2016-03-28 08:57:50
● 2016-09-09 08:26:20
○ 2026-04-12 05:59:10
○ 2026-05-11 09:30:16

○NSns5.dnsdun.net2016-09-09 → 2016-09-09 · 4 obs

○ 2016-03-28 08:57:50
● 2016-09-09 08:26:20
○ 2026-04-12 05:59:10
○ 2026-05-11 09:30:16

●NStoby.ns.cloudflare.com2026-05-11 → 2026-05-11 · 2 obs

○ 2026-04-12 05:59:10
● 2026-05-11 09:30:16

○MXmailstore1.secureserver.net2016-03-28 → 2016-03-28 · 3 obs

● 2016-03-28 08:57:50
○ 2016-09-09 08:26:20
○ 2026-05-11 09:30:16

○MXsmtp.secureserver.net2016-03-28 → 2016-03-28 · 3 obs

● 2016-03-28 08:57:50
○ 2016-09-09 08:26:20
○ 2026-05-11 09:30:16

●A104.21.78.2012026-05-11 → 2026-05-11 · 2 obs

○ 2026-04-12 05:59:10
● 2026-05-11 09:30:16

○A104.233.180.222016-09-09 → 2016-09-09 · 4 obs

○ 2016-03-28 08:57:50
● 2016-09-09 08:26:20
○ 2026-04-12 05:59:10
○ 2026-05-11 09:30:16

○A108.186.17.1192026-04-12 → 2026-04-12 · 3 obs

○ 2016-09-09 08:26:20
● 2026-04-12 05:59:10
○ 2026-05-11 09:30:16

●A172.67.137.1122026-05-11 → 2026-05-11 · 2 obs

○ 2026-04-12 05:59:10
● 2026-05-11 09:30:16

○A198.2.231.2262015-07-26 → 2015-12-06 · 4 obs

● 2015-07-26 01:47:48
● 2015-12-06 00:20:08
○ 2016-03-28 08:57:50
○ 2026-05-11 09:30:16

●A2606:4700:3033::6815:4ec92026-05-11 → 2026-05-11 · 2 obs

○ 2026-04-12 05:59:10
● 2026-05-11 09:30:16

●A2606:4700:3037::ac43:89702026-05-11 → 2026-05-11 · 2 obs

○ 2026-04-12 05:59:10
● 2026-05-11 09:30:16

○A50.63.202.632016-03-28 → 2016-03-28 · 4 obs

○ 2015-12-06 00:20:08
● 2016-03-28 08:57:50
○ 2016-09-09 08:26:20
○ 2026-05-11 09:30:16

🔍 DNS Trace

📋 Delegation Chain

Zone	Nameservers	Glue
com	a.gtld-servers.net, b.gtld-servers.net, c.gtld-servers.net, d.gtld-servers.net...	-
51classes.com	toby.ns.cloudflare.com, brenna.ns.cloudflare.com	12 records

✅ Authoritative Response

Server:108.162.193.239

NS records: toby.ns.cloudflare.com, brenna.ns.cloudflare.com

🔒 DNSSEC Status

⚠️ Insecure (no DNSSEC)

No DS record for 51classes.com (unsigned zone)

⏱️ Timing

Total: 448ms | Queries: -

📄 Records

Type	Count	Sample Data
A	2	`104.21.78.201, 172.67.137.112`
AAAA	2	`2606:4700:3033::6815:4ec9, 2606:4700:3037::ac43:8970`
NS	2	`brenna.ns.cloudflare.com, toby.ns.cloudflare.com`
HTTPS	1	`{"priority":1,"target":".","alpn":["h3",`
SOA	1	`brenna.ns.cloudflare.com dns.cloudflare.`

📌 Glue Records Collected

Total: 12

Out-of-bailiwick: 12 (toby.ns.cloudflare.com, toby.ns.cloudflare.com, toby.ns.cloudflare.com...)

Analysis

IP Addresses

51classes.com resolves to four IPs: 2606:4700:3033::6815:4ec9, 2606:4700:3037::ac43:8970, 104.21.78.201 and 172.67.137.112.

Other host names, for instance acquamarinha.com.br, converse-assistant.com, barclay.co, pinaslegitsite.com and denizlisosyetepazari.com share IP numbers with 51classes.com.

Name Servers

51classes.com has two name servers: brenna.ns.cloudflare.com and toby.ns.cloudflare.com.

51classes.com shares the same name server setup as other domains, for example zghbgy.com, eiill.com, odqa.cn, johnbeckley.com and bairuan.net.

51classes.com shares some name servers with other domains, for example situshanabet.xyz, ttiapps.com, drtsaiplasticsurgery.com, hellobra6.com and app-falcon.pro.

These name servers are commonly used together with ollie.ns.cloudflare.com and aaden.ns.cloudflare.com.

Host names with six IP numbers: brenna.ns.cloudflare.com points to: 2606:4700:50::a29f:26b0, 2803:f800:50::6ca2:c2b0, 2a06:98c1:50::ac40:22b0, 108.162.194.176, 162.159.38.176 and 172.64.34.176; toby.ns.cloudflare.com points to: 2606:4700:58::adf5:3bef, 2803:f800:50::6ca2:c1ef, 2a06:98c1:50::ac40:21ef, 108.162.193.239, 172.64.33.239 and 173.245.59.239.

51classes.com - robtex.com

51classes.com

com

Same first word

DNS History

🔍 DNS Trace

📋 Delegation Chain

✅ Authoritative Response

🔒 DNSSEC Status

⏱️ Timing

📄 Records

📌 Glue Records Collected

Analysis

IP Addresses

Name Servers

`51classes.com`

`com`