All IP Ranges
81.0.0.0/8
AS2856 | 81.128.0.0/11

81.128.0.0/11

AS2856 · British Telecommunications PLC

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Summary

Country	United Kingdom
Domain	bt.com
ASN	AS2856
Registry	RIPE
ID	UK-BT-20020725

WHOIS Details

inetnum:        81.128.0.0 - 81.159.255.255
org:            ORG-BPIS1-RIPE
netname:        UK-BT-20020725
country:        GB
admin-c:        FLS15-RIPE
tech-c:         FLS15-RIPE
status:         ALLOCATED PA
mnt-by:         RIPE-NCC-HM-MNT
mnt-by:         BTNET-INFRA-MNT
mnt-routes:     BTNET-INFRA-MNT
created:        2002-09-10T14:35:54Z
last-modified:  2024-03-11T16:17:01Z
source:         RIPE
abuse-email:    abuse@bt.com
abuse-c:        AR13878-RIPE
abuse-org:      ORG-BPIS1-RIPE

organisation:   ORG-BPIS1-RIPE
org-name:       British Telecommunications PLC
country:        GB
org-type:       LIR
address:        PP1, Floor1, Orion, Adastral Park, Martlesham Heath
address:        IP5 3RE
address:        Ipswich
address:        UNITED KINGDOM
phone:          +44 (0)20 7356 5000
abuse-c:        AR13878-RIPE
mnt-ref:        BTNET-MNT
mnt-ref:        BTNET-INFRA-MNT
mnt-ref:        RIPE-NCC-HM-MNT
mnt-by:         RIPE-NCC-HM-MNT
mnt-by:         BTNET-INFRA-MNT
admin-c:        FLS15-RIPE
admin-c:        MS35380-RIPE
admin-c:        GF1231-RIPE
created:        2004-04-17T12:11:50Z
last-modified:  2025-03-24T17:20:04Z
source:         RIPE
e-mail:         ipaddman@bt.com
abuse-email:    abuse@bt.com
abuse-c:        AR13878-RIPE
abuse-org:      undefined

role:           BT IP Address Admin
address:        PP 1, Floor 1
address:        Orion Building
address:        Adastral Park
address:        Martlesham Heath
address:        Ipswich
address:        IP5 3RE
address:        UK
e-mail:         ipaddman@bt.com
e-mail:         abuse@bt.com
remarks:        
remarks:        
nic-hdl:        FLS15-RIPE
mnt-by:         BTNET-INFRA-MNT
created:        2002-08-29T06:26:48Z
last-modified:  2023-06-21T11:23:36Z
source:         RIPE

route:          81.128.0.0/11
descr:          BT Public Internet Service
origin:         AS2856
mnt-by:         BTNET-INFRA-MNT
notify:         ip.address.admin@bt.com
created:        2002-10-22T13:45:17Z
last-modified:  2014-07-31T07:51:30Z
source:         RIPE

Overlapping Ranges

BGP prefixes that are contained by 81.128.0.0/11

Range	ASN	Company	Num of IPs
81.128.0.0/12	AS2856	BT Infrastructure Layer	1,048,576

Nearby Ranges

BGP prefixes that overlap with 81.0.0.0/8

Range	ASN	Company	Num of IPs
81.128.0.0/12	AS2856	BT Infrastructure Layer	1,048,576
81.96.0.0/12	AS5089	Virgin Media Limited	1,048,576
81.212.0.0/14	AS9121	Turk Telekomunikasyon Anonim Sirketi	262,144
81.76.0.0/14	AS5378	Vodafone Limited	262,144
81.64.0.0/14	AS15557	Societe Francaise Du Radiotelephone - SFR SA	262,144
81.204.0.0/14	AS1136	KPN B.V.	262,144
81.68.0.0/14	AS45090	Tencent Cloud Computing (Beijing) Co., Ltd	262,144
81.178.0.0/15	AS13285	TalkTalk Communications Limited	131,072
81.60.0.0/15	AS12430	VODAFONE ONO, S.A.	131,072
81.56.0.0/15	AS29447	Free SAS	131,072
81.82.0.0/15	AS6848	Telenet BV	131,072
81.164.0.0/15	AS6848	Telenet BV	131,072
81.62.0.0/15	AS3303	Swisscom (Schweiz) AG	131,072
81.182.0.0/15	AS5483	Magyar Telekom Plc.	131,072
81.166.0.0/15	AS29695	Lyse Tele AS	131,072
81.192.0.0/16	AS6713	Office National des Postes et Telecommunications ONPT (Maroc Telecom) / IAM	65,536
81.198.0.0/16	AS24921	SIA Tet	65,536
81.193.0.0/16	AS3243	MEO - SERVICOS DE COMUNICACOES E MULTIMEDIA S.A.	65,536
81.185.0.0/16	AS15557	Societe Francaise Du Radiotelephone - SFR SA	65,536
81.195.0.0/16	AS8359	MTS PJSC	65,536
81.32.0.0/16	AS3352	Telefonica de Espana SAU	65,536
81.44.0.0/16	AS3352	Telefonica de Espana SAU	65,536
81.87.0.0/16	AS786	Jisc Services Limited	65,536
81.36.0.0/16	AS3352	Telefonica de Espana SAU	65,536
81.38.0.0/16	AS3352	Telefonica de Espana SAU	65,536
81.202.0.0/16	AS6739	Cableuropa - ONO	65,536
81.190.0.0/16	AS21021	Multimedia Polska Sp. z o.o.	65,536
81.34.0.0/16	AS3352	Telefonica de Espana SAU	65,536
81.37.0.0/16	AS3352	Telefonica de Espana SAU	65,536
81.61.0.0/16	AS6739	ONO_HFC	65,536
81.40.0.0/16	AS3352	Telefonica de Espana SAU	65,536
81.35.0.0/16	AS3352	Telefonica de Espana SAU	65,536
81.39.0.0/16	AS3352	Telefonica de Espana SAU	65,536
81.220.0.0/16	AS15557	Societe Francaise Du Radiotelephone - SFR SA	65,536
81.187.0.0/16	AS20712	Andrews & Arnold Ltd	65,536
81.184.0.0/16	AS6739	VODAFONE ONO, S.A.	65,536
81.33.0.0/16	AS3352	Telefonica de Espana SAU	65,536
81.80.0.0/16	AS3215	Orange S.A.	65,536
81.188.0.0/16	AS3257	GTT Communications Belgium N.V.	65,536
81.126.0.0/16	AS3269	Telecom Italia S.p.A.	65,536
81.196.0.0/16	AS8708	DIGI ROMANIA S.A.	65,536
81.219.0.0/16	AS12741	Netia SA	65,536
81.189.0.0/16	AS8437	Network of Hutchison Drei Austria GmbH	65,536
81.57.0.0/16	AS29447	Iliad / Free SAS	65,536
81.218.0.0/16	AS8551	Bezeq International Ltd.	65,536
81.197.0.0/16	AS719	Elisa Oyj	65,536
81.198.0.0/16	AS12578	SIA Tet	65,536
81.191.0.0/16	AS2116	GLOBALCONNECT AS	65,536
81.81.0.0/16	AS1267	WIND TRE S.P.A.	65,536

Hosted domains

There are 8,166 domain names hosted across 3,067 IP addresses on this ASN. Checkout our API to access full domain hosting information.

IP Address	Domain	Domains on this IP
81.145.31.210	gdchesterfield.co.uk	881
81.145.16.13	cqtimes.org.uk	260
81.145.31.217	hdsscunthorpe.uk	251
81.144.251.155	campingandcaravanningclub.co.uk	99
81.144.162.21	cymrufuels.com	78
81.145.16.53	mustardpotvets.com	75
81.144.218.84	rootstheatre.co.uk	61
81.136.181.36	uksap.com	59
81.133.245.70	expressroofinghomeimprovements.co.uk	49
81.128.180.98	coresoundsdisco.co.uk	42
81.145.58.165	screenpayroll.co.uk	42
81.144.179.205	magianltd.com	41
81.145.167.201	go-tcha-evolve.co.uk	36
81.144.224.25	brandontoolhire.com	35
81.145.31.222	southerngaragedoorrepairs.co.uk	31
81.150.25.196	clearinternetsolutions.info	29
81.150.7.16	footprintzltd.com	29
81.128.250.13	ellandsmiles.co.uk	26
81.128.216.75	mondaysupport.com	25
81.149.189.167	raidspeed.co.uk	24

Hosted domains API

Our Hosted Domains API, or Reverse IP API returns a full list of domains that are hosted on a single IP address.

Useful for Cybersecurity

Read more

Pingable IPs

942,813 IPs in this range replied to an ICMP ping during our most recent internet scan. Learn more.

IP Address	ASN	Details
81.139.132.181	AS2856 British Telecommunications PLC	`3.25ms` from London, GB
81.139.163.187	AS2856 British Telecommunications PLC	`5.67ms` from London, GB
81.139.215.184	AS2856 British Telecommunications PLC	`5.48ms` from London, GB
81.139.141.110	AS2856 British Telecommunications PLC	`3.99ms` from London, GB
81.138.100.121	AS2856 British Telecommunications PLC	`7.22ms` from London, GB
81.139.168.12	AS2856 British Telecommunications PLC	`4.88ms` from London, GB
81.139.148.36	AS2856 British Telecommunications PLC	`12.01ms` from Erith, GB
81.139.216.130	AS2856 British Telecommunications PLC	`3.16ms` from Erith, GB
81.138.157.25	AS2856 British Telecommunications PLC	`3.54ms` from London, GB
81.138.75.78	AS2856 British Telecommunications PLC	`5.13ms` from London, GB
81.138.77.177	AS2856 British Telecommunications PLC	`5.61ms` from London, GB
81.138.64.217	AS2856 British Telecommunications PLC	`10.37ms` from London, GB
81.138.152.134	AS2856 British Telecommunications PLC	`8.06ms` from Erith, GB
81.138.237.230	AS2856 British Telecommunications PLC	`50.76ms` from London, GB
81.139.218.2	AS2856 British Telecommunications PLC	`4.58ms` from London, GB
81.138.220.206	AS2856 British Telecommunications PLC	`4.96ms` from London, GB
81.139.128.1	AS2856 British Telecommunications PLC	`0.66ms` from London, GB
81.139.41.210	AS2856 British Telecommunications PLC	`1.18ms` from London, GB
81.139.142.249	AS2856 British Telecommunications PLC	`6.90ms` from London, GB
81.138.164.238	AS2856 British Telecommunications PLC	`17.37ms` from London, GB
81.138.89.129	AS2856 British Telecommunications PLC	`6.07ms` from Erith, GB
81.138.86.238	AS2856 British Telecommunications PLC	`8.52ms` from London, GB
81.138.150.137	AS2856 British Telecommunications PLC	`25.50ms` from London, GB
81.139.164.64	AS2856 British Telecommunications PLC	`5.48ms` from London, GB
81.139.145.40	AS2856 British Telecommunications PLC	`5.87ms` from London, GB

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
1.91.8.75	AS17429 BEIJING GEHUA CATV NETWORK CO.LTD	`5.20ms` from Beijing, CN
54.212.155.139	AS16509 Amazon.com, Inc.	`0.21ms` from Boardman, US
130.131.38.91	AS8075 Microsoft Corporation	`0.26ms` from Chicago, US
3.136.72.139	AS16509 Amazon.com, Inc.	`0.18ms` from Columbus, US
83.100.197.155	AS12390 KCOM GROUP LIMITED	`3.06ms` from Manchester, GB
15.156.83.11	AS16509 Amazon.com, Inc.	`0.68ms` from Montreal, CA
62.228.13.187	AS6866 Cyprus Telecommunications Authority	`2.45ms` from Nicosia, CY
68.198.180.219	AS6128 Cablevision Systems Corp.	`2.24ms` from Piscataway, US
24.21.209.171	AS7922 Comcast Cable Communications, LLC	`2.50ms` from Portland, US
34.194.210.27	AS14618 Amazon.com, Inc.	`0.15ms` from Reston, US
94.99.221.171	AS25019 Saudi Telecom Company JSC	`2.69ms` from Riyadh, SA
73.241.8.123	AS7922 Comcast Cable Communications, LLC	`7.09ms` from Santa Clara, US
83.222.176.139	AS29622 ICON Ltd	`9.21ms` from Sofia, BG
35.243.98.219	AS396982 Google LLC	`0.14ms` from Tokyo, JP
153.216.208.43	AS4713 NTT DOCOMO BUSINESS,Inc.	`2.96ms` from Tokyo, JP
65.182.220.203	AS20021 Ntirety, Inc.	`4.91ms` from Ashburn, US
179.220.130.251	AS28573 Claro NXT Telecomunicacoes Ltda	`18.90ms` from Brasilia, BR
122.163.157.203	AS24560 Bharti Airtel Ltd., Telemedia Services	`9.22ms` from Delhi, IN
84.186.28.107	AS3320 Deutsche Telekom AG	`7.10ms` from Frankfurt am Main, DE
217.231.189.43	AS3320 Deutsche Telekom AG	`9.26ms` from Frankfurt am Main, DE
116.118.50.11	AS63760 AZDIGI Corporation	`0.51ms` from Ho Chi Minh City, VN
75.73.225.187	AS7922 Comcast Cable Communications, LLC	`3.35ms` from Minneapolis, US
120.193.73.59	AS9808 China Mobile Communications Group Co., Ltd.	`5.30ms` from Nanjing, CN
97.74.13.171	AS26496 GoDaddy.com, LLC	`1.03ms` from Phoenix, US
64.85.2.219	AS20271 Dogear/Packet Partners	`6.91ms` from Seattle, US

Traceroute

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

traceroute -a -n -q1 -f5 81.156.175.150

traceroute to 81.156.175.150 (81.156.175.150): 64 hops max, 52 byte packets

5 [AS2856] 62.6.204.162 2.532 ms

6 *

7 *

8 [AS2856] 81.156.175.150 17.264 ms

Measurement taken from

IPinfo ProbeNet in London, GB

On December 6th 2025

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