All IP Ranges
121.0.0.0/8
AS4766 | 121.128.0.0/12

121.128.0.0/12

AS4766 · Korea Telecom

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Summary

Country	South Korea
Domain	kt.com
ASN	AS4766
Parent Range	121.128.0.0/11
Registry	APNIC
ID	KORNET

WHOIS Details

inetnum:        121.128.0.0 - 121.159.255.255
netname:        KORNET
descr:          Korea Telecom
admin-c:        IM667-AP
tech-c:         IM667-AP
country:        KR
status:         ALLOCATED PORTABLE
mnt-by:         MNT-KRNIC-AP
mnt-irt:        IRT-KRNIC-KR
changed:        hostmaster@nic.or.kr 20170203
source:         APNIC

irt:            IRT-KRNIC-KR
address:        Seoul Songpa-gu Jungdae-ro 135
e-mail:         hostmaster@nic.or.kr
abuse-mailbox:  hostmaster@nic.or.kr
admin-c:        IM574-AP
tech-c:         IM574-AP
auth:           # Filtered
mnt-by:         MNT-KRNIC-AP
changed:        hostmaster@nic.or.kr 20150513
source:         APNIC

person:         IP Manager
address:        Gyeonggi-do Bundang-gu, Seongnam-si Buljeong-ro 90
country:        KR
phone:          +82-2-500-6630
e-mail:         kornet_ip@kt.com
nic-hdl:        IM667-AP
mnt-by:         MNT-KRNIC-AP
changed:        hostmaster@nic.or.kr 20170328
source:         APNIC

inetnum:        121.128.0.0 - 121.159.255.255
netname:        KORNET-KR
descr:          Korea Telecom
country:        KR
admin-c:        IA9-KR
tech-c:         IM9-KR
status:         ALLOCATED PORTABLE
mnt-by:         MNT-KRNIC-AP
mnt-irt:        IRT-KRNIC-KR
remarks:        This information has been partially mirrored by APNIC from
remarks:        KRNIC. To obtain more specific information, please use the
remarks:        KRNIC whois server at whois.krnic.net.
changed:        hostmaster@nic.or.kr
source:         KRNIC

person:         IP Manager
address:        Gyeonggi-do Bundang-gu, Seongnam-si Buljeong-ro 90
address:        
country:        KR
phone:          +82-2-500-6630
e-mail:         kornet_ip@kt.com
nic-hdl:        IA9-KR
mnt-by:         MNT-KRNIC-AP
changed:        hostmaster@nic.or.kr
source:         KRNIC

person:         IP Manager
address:        Gyeonggi-do Bundang-gu, Seongnam-si Buljeong-ro 90
address:        
country:        KR
phone:          +82-2-500-6630
e-mail:         kornet_ip@kt.com
nic-hdl:        IM9-KR
mnt-by:         MNT-KRNIC-AP
changed:        hostmaster@nic.or.kr
source:         KRNIC

Overlapping Ranges

BGP prefixes that contain 121.128.0.0/12

Range	ASN	Company	Num of IPs
121.128.0.0/11	AS131792	Korea Telecom	2,097,152
121.128.0.0/11	AS152214	Korea Telecom	2,097,152
121.128.0.0/11	AS17588	Korea Telecom	2,097,152
121.128.0.0/11	AS18023	Korea Telecom	2,097,152
121.128.0.0/11	AS18333	Korea Telecom	2,097,152
121.128.0.0/11	AS3786	Korea Telecom	2,097,152
121.128.0.0/11	AS38122	Korea Telecom	2,097,152
121.128.0.0/11	AS38126	Korea Telecom	2,097,152
121.128.0.0/11	AS38394	Korea Telecom	2,097,152
121.128.0.0/11	AS38395	Korea Telecom	2,097,152
121.128.0.0/11	AS38399	Korea Telecom	2,097,152
121.128.0.0/11	AS38412	Korea Telecom	2,097,152
121.128.0.0/11	AS38697	Korea Telecom	2,097,152
121.128.0.0/11	AS46002	Korea Telecom	2,097,152
121.128.0.0/11	AS4766	Korea Telecom	2,097,152
121.128.0.0/11	AS9526	Korea Telecom	2,097,152
121.128.0.0/11	AS9530	Korea Telecom	2,097,152
121.128.0.0/11	AS9638	Korea Telecom	2,097,152
121.128.0.0/11	AS9647	Korea Telecom	2,097,152
121.128.0.0/11	AS9696	Korea Telecom	2,097,152
121.128.0.0/11	AS9776	Korea Telecom	2,097,152
121.128.0.0/11	AS9856	Korea Telecom	2,097,152
121.128.0.0/11	AS9870	Korea Telecom	2,097,152

Nearby Ranges

BGP prefixes that overlap with 121.0.0.0/8

Range	ASN	Company	Num of IPs
121.128.0.0/11	AS38399	Korea Telecom	2,097,152
121.128.0.0/11	AS3786	Korea Telecom	2,097,152
121.160.0.0/11	AS38404	Korea Telecom	2,097,152
121.160.0.0/11	AS55622	Korea Telecom	2,097,152
121.160.0.0/11	AS17859	Korea Telecom	2,097,152
121.128.0.0/11	AS131792	Korea Telecom	2,097,152
121.128.0.0/11	AS38412	Korea Telecom	2,097,152
121.160.0.0/11	AS55615	Korea Telecom	2,097,152
121.160.0.0/11	AS17862	Korea Telecom	2,097,152
121.160.0.0/11	AS38415	Korea Telecom	2,097,152
121.160.0.0/11	AS23582	Korea Telecom	2,097,152
121.128.0.0/11	AS38394	Korea Telecom	2,097,152
121.160.0.0/11	AS10167	Korea Telecom	2,097,152
121.160.0.0/11	AS38431	Korea Telecom	2,097,152
121.160.0.0/11	AS38427	Korea Telecom	2,097,152
121.128.0.0/11	AS38395	Korea Telecom	2,097,152
121.128.0.0/11	AS9870	Korea Telecom	2,097,152
121.128.0.0/11	AS17588	Korea Telecom	2,097,152
121.128.0.0/11	AS152214	Korea Telecom	2,097,152
121.160.0.0/11	AS3786	Korea Telecom	2,097,152
121.160.0.0/11	AS38391	Korea Telecom	2,097,152
121.160.0.0/11	AS38392	Korea Telecom	2,097,152
121.160.0.0/11	AS9778	Korea Telecom	2,097,152
121.160.0.0/11	AS9530	Korea Telecom	2,097,152
121.160.0.0/11	AS38089	Korea Telecom	2,097,152
121.128.0.0/11	AS9647	Korea Telecom	2,097,152
121.160.0.0/11	AS38087	Korea Telecom	2,097,152
121.128.0.0/11	AS18333	Korea Telecom	2,097,152
121.160.0.0/11	AS4766	Korea Telecom	2,097,152
121.160.0.0/11	AS38093	Korea Telecom	2,097,152
121.128.0.0/11	AS9638	Korea Telecom	2,097,152
121.128.0.0/11	AS18023	Korea Telecom	2,097,152
121.160.0.0/11	AS9708	Korea Telecom	2,097,152
121.160.0.0/11	AS9684	Korea Telecom	2,097,152
121.128.0.0/11	AS38122	Korea Telecom	2,097,152
121.128.0.0/11	AS9776	Korea Telecom	2,097,152
121.128.0.0/11	AS9530	Korea Telecom	2,097,152
121.128.0.0/11	AS46002	Korea Telecom	2,097,152
121.128.0.0/11	AS38697	Korea Telecom	2,097,152
121.128.0.0/11	AS9526	Korea Telecom	2,097,152
121.160.0.0/11	AS9843	Korea Telecom	2,097,152
121.128.0.0/11	AS9696	Korea Telecom	2,097,152
121.160.0.0/11	AS45399	Korea Telecom	2,097,152
121.160.0.0/11	AS38696	Korea Telecom	2,097,152
121.128.0.0/11	AS9856	Korea Telecom	2,097,152
121.128.0.0/11	AS38126	Korea Telecom	2,097,152
121.128.0.0/11	AS4766	Korea Telecom	2,097,152
121.160.0.0/11	AS9647	Korea Telecom	2,097,152
121.224.0.0/12	AS4134	CHINANET jiangsu province network	1,048,576
121.224.0.0/12	AS146966	CHINANET jiangsu province network	1,048,576

Hosted domains

There are 3,155 domain names hosted across 1,181 IP addresses on this ASN. Checkout our API to access full domain hosting information.

IP Address	Domain	Domains on this IP
121.140.43.236	supersolar.com	157
121.140.37.75	nothyunsuk.com	62
121.135.203.111	gibbeum.cn	13
121.141.70.19	bac.kr	12
121.138.248.144	ahnsahnghong.com	12
121.141.70.12	kitutennis.co.kr	10
121.138.248.69	heavenlymotherslove.org	8
121.129.210.102	cosmelone.com	8
121.134.13.79	ldap.or.kr	7
121.128.36.11	archiveglossary.co.kr	6
121.141.137.64	carrotjapan.kr	6
121.131.194.211	ktlc.co.kr	6
121.131.26.52	hsplant.co.kr	6
121.140.151.252	mcnex.com	6
121.136.95.140	n-telecom.kr	6
121.137.210.41	adsensezone.com	6
121.141.141.113	danceoffice.co.kr	5
121.141.19.228	meatmon.co.kr	5
121.136.237.239	kopress.kr	5
121.128.35.83	mattfli.cx	5

Hosted domains API

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Useful for Cybersecurity

Read more

Pingable IPs

542,454 IPs in this range replied to an ICMP ping during our most recent internet scan. Learn more.

IP Address	ASN	Details
121.131.108.12	AS4766 Korea Telecom	`1.28ms` from Seoul, KR
121.131.35.184	AS4766 Korea Telecom	`1.34ms` from Seoul, KR
121.131.101.30	AS4766 Korea Telecom	`1.23ms` from Seoul, KR
121.131.83.58	AS4766 Korea Telecom	`1.22ms` from Seoul, KR
121.131.44.42	AS4766 Korea Telecom	`1.41ms` from Seoul, KR
121.130.248.72	AS4766 Korea Telecom	`1.66ms` from Seoul, KR
121.130.177.254	AS4766 Korea Telecom	`1.64ms` from Seoul, KR
121.131.98.61	AS4766 Korea Telecom	`1.25ms` from Seoul, KR
121.130.222.190	AS4766 Korea Telecom	`1.43ms` from Seoul, KR
121.130.172.78	AS4766 Korea Telecom	`1.59ms` from Seoul, KR
121.130.195.107	AS4766 Korea Telecom	`1.45ms` from Seoul, KR
121.130.186.27	AS4766 Korea Telecom	`1.86ms` from Seoul, KR
121.131.28.7	AS4766 Korea Telecom	`1.37ms` from Seoul, KR
121.131.38.62	AS4766 Korea Telecom	`1.01ms` from Seoul, KR
121.131.92.244	AS4766 Korea Telecom	`1.25ms` from Seoul, KR
121.130.130.223	AS4766 Korea Telecom	`1.45ms` from Seoul, KR
121.130.226.133	AS4766 Korea Telecom	`1.52ms` from Seoul, KR
121.130.233.47	AS4766 Korea Telecom	`1.38ms` from Seoul, KR
121.130.144.254	AS4766 Korea Telecom	`1.74ms` from Seoul, KR
121.131.113.89	AS4766 Korea Telecom	`1.33ms` from Seoul, KR
121.131.8.30	AS4766 Korea Telecom	`1.30ms` from Seoul, KR
121.130.140.14	AS4766 Korea Telecom	`1.38ms` from Seoul, KR
121.131.114.30	AS4766 Korea Telecom	`1.30ms` from Seoul, KR
121.130.152.46	AS4766 Korea Telecom	`1.13ms` from Seoul, KR
121.130.192.65	AS4766 Korea Telecom	`1.74ms` from Seoul, KR

Other Pingable IPs

Below is a random selection of 25 IPs that replied to an ICMP ping during our most recent internet scan.

IP Address	ASN	Details
121.20.148.12	AS4837 CHINA UNICOM China169 Backbone	`15.01ms` from Beijing, CN
184.57.33.12	AS10796 Charter Communications Inc	`7.87ms` from Columbus, US
20.9.107.220	AS8075 Microsoft Corporation	`0.20ms` from Des Moines, US
76.30.67.108	AS7922 Comcast Cable Communications, LLC	`5.67ms` from Houston, US
175.164.121.76	AS4837 CHINA UNICOM China169 Backbone	`3.56ms` from Liaoyang, CN
47.136.76.252	AS5650 Frontier Communications of America, Inc.	`6.17ms` from Los Angeles, US
83.40.239.204	AS3352 TELEFONICA DE ESPANA S.A.U.	`9.18ms` from Madrid, ES
178.81.230.12	AS35819 Etihad Etisalat, a joint stock company	`4.07ms` from Manama, BH
98.242.214.92	AS7922 Comcast Cable Communications, LLC	`6.36ms` from Miami, US
95.229.189.108	AS3269 Telecom Italia S.p.A.	`2.13ms` from Milan, IT
222.101.80.188	AS4766 Korea Telecom	`1.47ms` from Seoul, KR
83.251.12.220	AS1257 Tele2 Sverige AB	`15.07ms` from Stockholm, SE
124.141.181.60	AS9824 JCOM Co., Ltd.	`10.91ms` from Tokyo, JP
66.7.143.140	AS3257 GTT Communications Inc.	`0.15ms` from Atlanta, US
35.87.107.172	AS16509 Amazon.com, Inc.	`0.15ms` from Boardman, US
24.12.203.172	AS7922 Comcast Cable Communications, LLC	`6.83ms` from Chicago, US
123.145.83.220	AS4837 CHINA UNICOM China169 Backbone	`2.36ms` from Chongqing, CN
39.45.239.28	AS17557 Pakistan Telecommunication Company Limited	`10.74ms` from Lahore, PK
213.98.164.236	AS3352 TELEFONICA DE ESPANA S.A.U.	`1.61ms` from Madrid, ES
217.13.54.92	AS31221 nLighten France SAS	`3.05ms` from Marseille, FR
182.91.57.76	AS4837 CHINA UNICOM China169 Backbone	`6.91ms` from Nanning, CN
223.134.81.28	AS2527 Sony Network Communications Inc.	`1.48ms` from Osaka, JP
3.224.39.60	AS14618 Amazon.com, Inc.	`0.14ms` from Reston, US
34.195.222.60	AS14618 Amazon.com, Inc.	`0.21ms` from Reston, US
52.44.245.220	AS14618 Amazon.com, Inc.	`0.18ms` from Reston, US

Traceroute

Below is a recent traceroute taken from the IPinfo ProbeNet to an IP in this range. Learn more.

traceroute -a -n -q1 121.130.97.254

traceroute to 121.130.97.254 (121.130.97.254): 64 hops max, 52 byte packets

1 [AS31898] 140.91.214.47 0.063 ms

2 [AS4766] 218.145.32.254 0.777 ms

3 *

4 *

5 [AS4766] 112.174.104.70 1.965 ms

6 *

7 *

8 [AS4766] 121.130.97.254 1.467 ms

Measurement taken from

IPinfo ProbeNet in Seoul, KR

On October 30th 2025

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