`51study.org`

DNSSEC	⚠️ Not signed
A	2606:4700:3032::6815:1aa2^{🇺🇸 Cloudflare2606:4700:3032::/48 , Inc. 101 Townsend Street, San Francisco, California 94107, US} ✓ In HTTPS hints
A	2606:4700:3035::ac43:8932^{🇺🇸 Cloudflare2606:4700:3035::/48 , Inc. 101 Townsend Street, San Francisco, California 94107, US} ✓ In HTTPS hints
A	104.21.26.162^{Cloudflare104.21.16.0/20 , Inc. 101 Townsend Street, San Francisco, California 94107, US} ✓ In HTTPS hints
A	172.67.137.50^{🇺🇸 Cloudflare172.67.128.0/20 , Inc. 101 Townsend Street, San Francisco, California 94107, US} ✓ In HTTPS hints
NS	`ignacio.ns.cloudflare.com` ⭐
		A	2606:4700:58::a29f:2c52^{🇺🇸 Cloudflare2606:4700:50::/44 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`ignacio.ns.cloudflare.com`
		A	2803:f800:50::6ca2:c352^{🇨🇷 Cloudflare2803:f800:50::/45 LACNIC generated route6 for CloudFlare Latin America S.R.L}
			PTR	`ignacio.ns.cloudflare.com`
		A	2a06:98c1:50::ac40:2352^{🇺🇸 Cloudflare2a06:98c1:50::/45}
			PTR	`ignacio.ns.cloudflare.com`
		A	108.162.195.82^{🇺🇸 Cloudflare108.162.195.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`ignacio.ns.cloudflare.com`
		A	162.159.44.82^{Cloudflare162.159.32.0/20 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`ignacio.ns.cloudflare.com`
		A	172.64.35.82^{🇺🇸 Cloudflare172.64.35.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`ignacio.ns.cloudflare.com`
NS	`miki.ns.cloudflare.com`
		A	2606:4700:50::adf5:3aca^{🇺🇸 Cloudflare2606:4700:50::/44 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`miki.ns.cloudflare.com`
		A	2803:f800:50::6ca2:c0ca^{🇨🇷 Cloudflare2803:f800:50::/45 LACNIC generated route6 for CloudFlare Latin America S.R.L}
			PTR	`miki.ns.cloudflare.com`
		A	2a06:98c1:50::ac40:20ca^{🇺🇸 Cloudflare2a06:98c1:50::/45}
			PTR	`miki.ns.cloudflare.com`
		A	108.162.192.202^{🇺🇸 Cloudflare108.162.192.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`miki.ns.cloudflare.com`
		A	172.64.32.202^{🇺🇸 Cloudflare172.64.32.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`miki.ns.cloudflare.com`
		A	173.245.58.202^{🇺🇸 Cloudflare173.245.58.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`miki.ns.cloudflare.com`
HTTPS	HTTP/3, HTTP/2 ✓ hints match
		IPv4 hints	104.21.26.162, 172.67.137.50
		IPv6 hints	2606:4700:3032::6815:1aa2, 2606:4700:3035::ac43:8932
		ECH	X25519, HKDF-SHA256 + AES-128-GCM draft, id=228, name=cloudflare-ech.com
SOA	`ignacio.ns.cloudflare.com`dns@cloudflare.com serial=2407459387

`org`

	DNSSEC	🔒 Signed (DS record present)
	NS	`a0.org.afilias-nst.info` ⭐ ⚠️ Not in parent delegation
	NS	`a2.org.afilias-nst.info` ⚠️ Not in parent delegation
	NS	`b0.org.afilias-nst.org`
	NS	`b2.org.afilias-nst.org`
	NS	`c0.org.afilias-nst.info` ⚠️ Not in parent delegation
	NS	`d0.org.afilias-nst.org`
	SOA	`a0.org.afilias-nst.info`hostmaster@donuts.email serial=1785504079

Same first word

51study.net.cn

51study.org

51study.net

51study.com

DNS History

16 records (6 active, 10 former)

●NSignacio.ns.cloudflare.com2026-05-25 → 2026-07-31 · 3 obs

○ 2017-06-02 08:30:50
● 2026-05-25 21:07:20
● 2026-07-31 14:03:24

●NSmiki.ns.cloudflare.com2026-05-25 → 2026-07-31 · 3 obs

○ 2017-06-02 08:30:50
● 2026-05-25 21:07:20
● 2026-07-31 14:03:24

○NSns15.xincache.com2015-06-04 → 2017-06-02 · 4 obs

● 2015-06-04 08:16:22
● 2017-06-02 08:30:50
○ 2026-05-25 21:07:20
○ 2026-07-31 14:03:24

○NSns16.xincache.com2015-06-04 → 2017-06-02 · 4 obs

● 2015-06-04 08:16:22
● 2017-06-02 08:30:50
○ 2026-05-25 21:07:20
○ 2026-07-31 14:03:24

○MXmxbiz1.qq.com2015-10-23 → 2017-06-02 · 4 obs

● 2015-10-23 02:17:40
● 2017-06-02 08:30:50
○ 2026-05-25 21:07:20
○ 2026-07-31 14:03:24

○MXmxbiz2.qq.com2015-10-23 → 2017-06-02 · 4 obs

● 2015-10-23 02:17:40
● 2017-06-02 08:30:50
○ 2026-05-25 21:07:20
○ 2026-07-31 14:03:24

●A104.21.26.1622026-05-25 → 2026-07-31 · 5 obs

● 2026-05-25 21:07:20
● 2026-06-13 15:38:02
○ 2026-07-02 05:20:28
● 2026-07-13 12:39:14
● 2026-07-31 14:03:24

●A172.67.137.502026-05-25 → 2026-07-31 · 5 obs

● 2026-05-25 21:07:20
● 2026-06-13 15:38:02
○ 2026-07-02 05:20:28
● 2026-07-13 12:39:14
● 2026-07-31 14:03:24

○A188.114.96.02026-07-02 → 2026-07-02 · 4 obs

○ 2026-06-13 15:38:02
● 2026-07-02 05:20:28
○ 2026-07-13 12:39:14
○ 2026-07-31 14:03:24

○A188.114.97.02026-07-02 → 2026-07-02 · 4 obs

○ 2026-06-13 15:38:02
● 2026-07-02 05:20:28
○ 2026-07-13 12:39:14
○ 2026-07-31 14:03:24

●A2606:4700:3032::6815:1aa22026-07-13 → 2026-07-31 · 3 obs

○ 2026-07-02 05:20:28
● 2026-07-13 12:39:14
● 2026-07-31 14:03:24

●A2606:4700:3035::ac43:89322026-07-13 → 2026-07-31 · 3 obs

○ 2026-07-02 05:20:28
● 2026-07-13 12:39:14
● 2026-07-31 14:03:24

○A2606:4700:3036::ac43:89322026-05-25 → 2026-06-13 · 4 obs

● 2026-05-25 21:07:20
● 2026-06-13 15:38:02
○ 2026-07-02 05:20:28
○ 2026-07-31 14:03:24

○A2606:4700:3037::6815:1aa22026-05-25 → 2026-06-13 · 4 obs

● 2026-05-25 21:07:20
● 2026-06-13 15:38:02
○ 2026-07-02 05:20:28
○ 2026-07-31 14:03:24

○A2a06:98c1:3120::2026-07-02 → 2026-07-02 · 4 obs

○ 2026-06-13 15:38:02
● 2026-07-02 05:20:28
○ 2026-07-13 12:39:14
○ 2026-07-31 14:03:24

○A2a06:98c1:3121::2026-07-02 → 2026-07-02 · 4 obs

○ 2026-06-13 15:38:02
● 2026-07-02 05:20:28
○ 2026-07-13 12:39:14
○ 2026-07-31 14:03:24

🔍 DNS Trace

📋 Delegation Chain

Zone	Nameservers	Glue
org	b2.org.afilias-nst.org, d0.org.afilias-nst.org, b0.org.afilias-nst.org	-
51study.org	miki.ns.cloudflare.com, ignacio.ns.cloudflare.com	-

✅ Authoritative Response

Server:108.162.192.202

NS records: miki.ns.cloudflare.com, ignacio.ns.cloudflare.com

🔒 DNSSEC Status

⚠️ Insecure (no DNSSEC)

No DS record for 51study.org (unsigned zone)

⏱️ Timing

Total: 415ms | Queries: -

📄 Records

Type	Count	Sample Data
A	2	`172.67.137.50, 104.21.26.162`
AAAA	2	`2606:4700:3032::6815:1aa2, 2606:4700:3035::ac43:8932`
NS	2	`ignacio.ns.cloudflare.com, miki.ns.cloudflare.com`
HTTPS	1	`{"priority":1,"target":".","alpn":["h3",`
SOA	1	`ignacio.ns.cloudflare.com dns.cloudflare`

Analysis

IP Addresses

51study.org directs to four IP numbers, which are 104.21.26.162, 172.67.137.50, 2606:4700:3032::6815:1aa2 and 2606:4700:3035::ac43:8932.

561tyq.com, albertainjurylaw.com, mail.govarrestrecords.org plus two other host names have IP numbers in common with 51study.org.

Name Servers

Two name servers handle the delegation for 51study.org: ignacio.ns.cloudflare.com and miki.ns.cloudflare.com.

The name server configuration of 51study.org is shared with other domains, for instance longfaibus.com, amg-news.com, whmos.com and two others.

There is at least partial name server overlap between 51study.org and other domains — reykjavikattractions.is, arborvitae.xyz, chronovialentia.sbs and two more among them.

These name servers tend to appear in combination with the name servers aleena.ns.cloudflare.com, austin.ns.cloudflare.com, kelly.ns.cloudflare.com and mia.ns.cloudflare.com.

Hosts with 6 IP addresses each:

ignacio.ns.cloudflare.com resolves to 108.162.195.82, 162.159.44.82 and 172.64.35.82 among others, with 3 other IP addresses in total.

miki.ns.cloudflare.com resolves to 108.162.192.202, 172.64.32.202 and 173.245.58.202 among others, with 3 other IP addresses in total.

51study.org - robtex.com

51study.org

org

Same first word

DNS History

🔍 DNS Trace

📋 Delegation Chain

✅ Authoritative Response

🔒 DNSSEC Status

⏱️ Timing

📄 Records

Analysis

IP Addresses

Name Servers

`51study.org`

`org`