Czech Republic ASN Summary
The report below shows ASNs assigned to Czech Republic, ranked by the total number of IP addresses currently active on each network. Click on the ASN for full IP address information, whois details and more. You can also view our hosting report to see the networks ranked by how many domain names they host.
| ASN | Name | Num IPs |
|---|---|---|
| AS5610 | O2 Czech Republic, a.s. | 1,553,920 |
| AS5588 | T-Mobile Czech Republic a.s. | 1,261,312 |
| AS16019 | Vodafone Czech Republic a.s. | 1,208,064 |
| AS2852 | CESNET z.s.p.o. | 848,896 |
| AS44546 | ALFA TELECOM s.r.o. | 526,336 |
| AS13036 | T-Mobile Czech Republic a.s. | 352,256 |
| AS29208 | Dial Telecom, a.s. | 258,560 |
| AS30764 | PODA a.s. | 222,208 |
| AS2571 | DHL Information Services (Europe) s.r.o | 148,736 |
| AS28725 | CETIN a.s. | 133,888 |
| AS16246 | Nej.cz s.r.o. | 124,928 |
| AS25512 | CD-Telematika a.s. | 118,784 |
| AS15425 | PODA a.s. | 110,592 |
| AS25248 | RADIOKOMUNIKACE a.s. | 106,752 |
| AS12767 | T-Mobile Czech Republic a.s. | 67,072 |
| AS197451 | Brno University of Technology | 67,072 |
| AS31246 | SMART Comp. a.s. | 66,560 |
| AS9080 | Ipex Ltd. | 63,488 |
| AS24971 | Master Internet s.r.o. | 59,648 |
| AS28851 | Nordic Telecom s.r.o | 58,368 |
| AS15685 | CASABLANCA INT a.s. | 58,112 |
| AS12570 | itself s.r.o. | 57,856 |
| AS44489 | STARNET, s.r.o. | 52,992 |
| AS15935 | ha-vel internet s.r.o. | 52,480 |
| AS24806 | INTERNET CZ, a.s. | 45,824 |
| AS42908 | Nordic Telecom s.r.o | 41,984 |
| AS6740 | ADAPTIVITY s.r.o. | 41,984 |
| AS21430 | WIA spol. s.r.o. | 39,424 |
| AS39906 | CoProSys a.s. | 37,632 |
| AS25424 | InterneXt 2000, s.r.o. | 33,792 |
| AS39392 | SH.cz s.r.o. | 32,768 |
| AS41046 | Nej.cz s.r.o. | 32,768 |
| AS34093 | Nordic Telecom Regional s.r.o. | 29,696 |
| AS29134 | Webglobe, s.r.o. | 25,088 |
| AS43708 | METRONET s.r.o. | 24,064 |
| AS47232 | ISP Alliance a.s. | 23,040 |
| AS198605 | AVAST Software s.r.o. | 22,272 |
| AS43541 | VSHosting s.r.o. | 19,968 |
| AS42306 | Edera Group a.s. | 19,456 |
| AS34040 | TTNET s.r.o. | 19,456 |
| AS204860 | NetX Networks a.s. | 18,944 |
| AS39791 | Telco Pro Services, a. s. | 18,432 |
| AS24641 | FASTER CZ spol. s r.o. | 17,920 |
| AS49985 | IP4ISP z.s.p.o | 17,408 |
| AS8251 | FreeTel, s.r.o. | 17,408 |
| AS61296 | TechCom s.r.o. | 17,408 |
| AS196735 | JON.CZ s.r.o. | 16,384 |
| AS197197 | M.NET STUDENKA s. r. o. | 16,384 |
| AS196822 | SELECT SYSTEM, s.r.o. | 16,384 |
| AS29321 | CentroNet a.s. | 15,360 |
| AS20723 | AVONET, s.r.o. | 15,360 |
| AS57728 | HELIOS MB s.r.o. | 15,360 |
| AS51248 | Host-Telecom.com s.r.o. | 14,336 |
| AS207187 | TKR Jasek, s.r.o. | 14,336 |
| AS50113 | NTX Technologies s.r.o. | 13,824 |
| AS28972 | M-SOFT, spol. s r.o. | 13,312 |
| AS197013 | Sprintel s.r.o. | 12,800 |
| AS35592 | Coolhousing s.r.o. | 12,544 |
| AS20884 | O2 Czech Republic, a.s. | 12,288 |
| AS34315 | Dial Telecom, a.s. | 12,288 |
| AS15614 | Dragon Internet a.s. | 12,288 |
| AS48474 | Nordic Telecom Regional s.r.o. | 12,288 |
| AS50241 | UnitTelecom Ltd | 11,520 |
| AS43542 | OptoNet Communication, spol. s.r.o. | 11,264 |
| AS50698 | TETA s.r.o. | 11,264 |
| AS34080 | MIRAMO spol. s.r.o. | 11,264 |
| AS197019 | WEDOS Internet, a.s. | 11,264 |
| AS47834 | SOFTEX NCP, s.r.o. | 11,264 |
| AS196845 | Nordic Telecom s.r.o | 11,264 |
| AS35236 | 2 connect a.s. | 10,496 |
| AS198668 | Tlapnet s.r.o. | 10,496 |
| AS39761 | ABAK, Co.Ltd. | 10,240 |
| AS35361 | GREPA Networks s.r.o. | 10,240 |
| AS35214 | Nordic Telecom Regional s.r.o. | 10,240 |
| AS49106 | Opticom Group AO | 10,240 |
| AS43070 | JAW.cz s.r.o. | 9,728 |
| AS49931 | SITKOM spol. s r.o. | 9,728 |
| AS48574 | Planet A, a.s. | 9,216 |
| AS50025 | Net Television Ltd | 9,216 |
| AS197798 | Net-Connect s.r.o. | 9,216 |
| AS49889 | Crystal Telecom Ltd | 9,216 |
| AS48926 | Pe3ny Net s.r.o. | 9,216 |
| AS49101 | KABELOVA TELEVIZE CZ s.r.o. | 9,216 |
| AS200918 | Pavel Zizka | 8,704 |
| AS201476 | ISP Alliance a.s. | 8,704 |
| AS42000 | Futruy s.r.o. | 8,448 |
| AS57069 | Dempsey and Clark s.r.o. | 8,448 |
| AS43507 | RETE internet, s.r.o. | 8,192 |
| AS41088 | N SYS s.r.o. | 8,192 |
| AS49025 | PRO-ZETA a.s. | 8,192 |
| AS47493 | WMS s.r.o. | 8,192 |
| AS33943 | Cesky Bezdrat, s.r.o. | 8,192 |
| AS56566 | SATT a.s. | 8,192 |
| AS8913 | Mopos Communications A.S. | 8,192 |
| AS42189 | Druzstvo EUROSIGNAL | 8,192 |
| AS198002 | FDLnet.CZ, s.r.o. | 8,192 |
| AS35613 | NetDataComm, s.r.o. | 8,192 |
| AS57800 | Cadr-TV LLE TVRC | 8,192 |
| AS51420 | cyrilek.net .z.s. | 8,192 |
| AS51731 | GTT a.s. | 8,192 |
| AS202237 | Wic-Net, s.r.o. | 8,192 |
| AS25234 | ACTIVE 24, s.r.o. | 8,192 |
| AS43709 | SilesNet s.r.o. | 8,192 |
| AS50022 | Kristelecom Ltd. | 8,192 |
| AS57564 | Nordic Telecom Regional s.r.o. | 8,192 |
| AS51891 | GSP ltd. | 8,192 |
| AS8518 | RFE/RL, Inc., organizacni slozka | 7,936 |
| AS33883 | TRIOPTIMUM s.r.o. | 7,168 |
| AS204383 | SPCom s.r.o. | 7,168 |
| AS50825 | UVT Internet s.r.o. | 7,168 |
| AS35046 | OMEGA plus Chrudim s.r.o. | 7,168 |
| AS39235 | Nordic Telecom Regional s.r.o. | 7,168 |
| AS201730 | DataSpring s.r.o. | 7,168 |
| AS197296 | Maxtel s.r.o. | 6,656 |
| AS25192 | CZ.NIC, z.s.p.o. | 6,400 |
| AS29583 | Spinoco Czech Republic, a.s. | 6,400 |
| AS34222 | ZONER software, a.s | 6,144 |
| AS59479 | GEMNET s.r.o. | 6,144 |
| AS28905 | BECO Link,spol.s.r.o. | 6,144 |
| AS51428 | IRONNET Ltd. | 6,144 |
| AS198813 | SychrovNET s.r.o | 6,144 |
| AS47114 | SychrovNET s.r.o | 6,144 |
| AS207198 | Kabelova televize Koprivnice, s.r.o. | 6,144 |
| AS43413 | NEW TELEKOM, spol. s r.o. | 6,144 |
| AS44065 | NETAIR, s.r.o. | 6,144 |
| AS197307 | Core4Net, s.r.o. | 5,376 |
| AS202895 | TFnet s.r.o. | 5,120 |
| AS49767 | Nej.cz s.r.o. | 5,120 |
| AS41670 | hkfree.org z.s. | 5,120 |
| AS39790 | Web4U s.r.o. | 5,120 |
| AS30877 | Ariadna-Link CJSC | 5,120 |
| AS60592 | Gransy s.r.o. | 5,120 |
| AS39817 | OvaNet, a.s. | 5,120 |
| AS202618 | Rychly drat, s.r.o. | 5,120 |
| AS196843 | KHnet.info, z.s. | 5,120 |
| AS48494 | BUKO LTD | 5,120 |
| AS206548 | Tlap s.r.o. | 5,120 |
| AS207242 | NOEL, s.r.o. | 5,120 |
| AS41453 | SITEL spol. s r.o. | 5,120 |
| AS31349 | a-net Liberec s.r.o. | 5,120 |
| AS48661 | AIRWAYNET, a.s. | 5,120 |
| AS209810 | Netcore services s.r.o. | 4,864 |
| AS47110 | Cloud4com, a.s. | 4,608 |
| AS52092 | Alf servis, s.r.o. | 4,608 |
| AS29086 | GiTy, a.s. | 4,096 |
| AS39904 | MERIT GROUP a.s | 4,096 |
| AS198500 | Masarykova univerzita - Ustav vypocetni techniky | 4,096 |
| AS62099 | JM-Net, z.s. | 4,096 |
| AS198403 | Matrigo s.r.o. | 4,096 |
| AS196782 | Marek Smutny | 4,096 |
| AS47868 | SUPRO, spol. s r.o. | 4,096 |
| AS57287 | OtavaNet s.r.o. | 4,096 |
| AS57399 | LTnet, s.r.o | 4,096 |
| AS57294 | Internet Expert s.r.o. | 4,096 |
| AS57279 | Sauron CZ s.r.o. | 4,096 |
| AS56450 | Alberon Letohrad s.r.o | 4,096 |
| AS57188 | ORKA systems, s.r.o. | 4,096 |
| AS57496 | AIRESS CESKO s.r.o. | 4,096 |
| AS56456 | C2NET s.r.o. | 4,096 |
| AS197550 | Internet4you.cz, spol. s r.o. | 4,096 |
| AS48417 | ITS akciova spolecnost | 4,096 |
| AS60931 | LAN-Service Ltd. | 4,096 |
| AS51968 | NEOS v.o.s. | 4,096 |
| AS47269 | Core4Net, s.r.o. | 4,096 |
| AS198991 | TV Nova sro | 4,096 |
| AS49890 | ABLE agency, s.r.o. | 4,096 |
| AS56360 | TRINITY CZECH REPUBLIC, s.r.o. | 4,096 |
| AS44070 | MCnet, s.r.o. | 4,096 |
| AS204064 | ISP Alliance a.s. | 4,096 |
| AS52115 | JaroNet - services s.r.o. | 4,096 |
| AS21045 | K-net Technical International Group, s.r.o. | 4,096 |
| AS51800 | FIBER Network s.r.o. | 4,096 |
| AS197846 | Radovan Ochvat trading as SAO Computers | 4,096 |
| AS197029 | LAM plus s.r.o. | 4,096 |
| AS207167 | amccomp s.r.o. | 3,584 |
| AS34911 | ELDATA prazska s.r.o. | 3,584 |
| AS6881 | NIX.CZ z.s.p.o. | 3,328 |
| AS57760 | Kinet s.r.o. | 3,328 |
| AS62178 | MASTER IT Technologies, a.s. | 3,328 |
| AS43614 | Economia a.s. | 3,072 |
| AS56973 | VITKOVICE IT SOLUTIONS a.s. | 3,072 |
| AS48364 | Radim Pytela - AC Vyskov | 3,072 |
| AS34047 | Bystrov Dmitriy Sergeevich | 3,072 |
| AS197046 | FIXnet s.r.o. | 3,072 |
| AS198161 | Sokolovska uhelna, pravni nastupce, a.s. | 3,072 |
| AS44002 | Sys-DataCom s.r.o. | 3,072 |
| AS196861 | DIGITAL ACTION s.r.o. | 3,072 |
| AS200059 | AIRWEB, spol. s r.o. | 3,072 |
| AS34955 | Martin Vicenik | 3,072 |
| AS47727 | Warnet.cz s.r.o. | 3,072 |
| AS43037 | Seznam.cz, a.s. | 3,072 |
| AS49320 | Golitsyno Telecom Ltd | 3,072 |
| AS197879 | HelaPC s.r.o. | 3,072 |
| AS47317 | Web4ce, s.r.o. | 3,072 |
| AS203018 | PAMICO CZECH, s.r.o. | 3,072 |
| AS57077 | AB-NET s.r.o. | 3,072 |
| AS202921 | CC INTERNET s.r.o. | 3,072 |
| AS48298 | MINISTERSTVO VNITRA CR | 2,816 |
| AS198167 | Apptc.me s.r.o. | 2,816 |
| AS50398 | Fast Communication, s.r.o. | 2,560 |
| AS198977 | UnArtel s.r.o. | 2,560 |
| AS52058 | Michal Najman | 2,560 |
| AS51234 | Telecompany Fialka Ltd. | 2,560 |
| AS197206 | BusinessCom CZ spol. s r.o. | 2,304 |
| AS48960 | AQUA,a.s. | 2,304 |
| AS50301 | BrazdimNET s.r.o. | 2,304 |
| AS43203 | TELCONET s.r.o. | 2,304 |
| AS62011 | UNHfree.net z.s. | 2,048 |
| AS213057 | innogy Ceska republika a.s | 2,048 |
| AS213223 | GasNet, s.r.o. | 2,048 |
| AS21241 | Global Payments Europe, s.r.o. | 2,048 |
| AS44424 | Internet Mall, a.s. | 2,048 |
| AS51655 | Ilim Telecom Ltd. | 2,048 |
| AS52029 | Palanet s.r.o. | 2,048 |
| AS51525 | Informacionnuye technologiyi Ltd | 2,048 |
| AS200848 | Miroslav Holienka | 2,048 |
| AS211774 | ign.cz internet, s.r.o. | 2,048 |
| AS41030 | Jaroslav Novotny | 2,048 |
| AS52084 | ATL Obchodni s.r.o. | 2,048 |
| AS51524 | Ales Tesacek | 2,048 |
| AS52130 | LiveSport s.r.o. | 2,048 |
| AS210306 | ADV Computers s.r.o. | 2,048 |
| AS52154 | mjanik.net s.r.o. | 2,048 |
| AS52176 | TTC TELEKOMUNIKACE s.r.o. | 2,048 |
| AS51400 | SPOJE.NET s.r.o. | 2,048 |
| AS38952 | MAFRA, a.s. | 2,048 |
| AS31461 | Moravia IT s.r.o. | 2,048 |
| AS56427 | Michal Hradil | 2,048 |
| AS34049 | H-data, spol. s r.o. | 2,048 |
| AS51210 | KRAXNET s.r.o. | 2,048 |
| AS60529 | Miroslav Klement | 2,048 |
| AS197083 | K2 atmitec s.r.o. | 2,048 |
| AS197218 | PP Dmutrashko Evgeny Vitalievich | 2,048 |
| AS208906 | SYNOT ICT Services, a.s. | 2,048 |
| AS201548 | Milan Zelenka | 2,048 |
| AS44430 | MaRcom-Eko s.r.o. | 2,048 |
| AS201648 | Plzensky kraj | 2,048 |
| AS201654 | Web4Soft Internet s.r.o. | 2,048 |
| AS47949 | gsnet.cz s.r.o. | 2,048 |
| AS59970 | AmigoNet s.r.o. | 2,048 |
| AS59959 | SferiaNET.cz s.r.o. | 2,048 |
| AS43895 | Zentiva Group, a.s | 2,048 |
| AS47131 | PH, spol. s r. o. | 2,048 |
| AS43757 | ICZ a.s. | 2,048 |
| AS200114 | PRO-COMUNICATION s.r.o | 2,048 |
| AS63113 | Globecorp Networks | 2,048 |
| AS197393 | Ladislav Rudolf | 2,048 |
| AS50348 | KVADOS, a.s. | 2,048 |
| AS197442 | Nordic Telecom Regional s.r.o. | 2,048 |
| AS50163 | Altnet s.r.o. | 2,048 |
| AS202682 | G2 server CZ s.r.o. | 2,048 |
| AS208648 | Playground HUB s.r.o. | 2,048 |
| AS197542 | Jan Saulich | 2,048 |
| AS197565 | NHK Solutions s.r.o. | 2,048 |
| AS203165 | Statni pokladna Centrum sdilenych sluzeb, s.p. | 2,048 |
| AS196684 | VITALATIV, s.r.o. | 2,048 |
| AS57823 | INERCOM, s.r.o. | 2,048 |
| AS57798 | IT-Net ltd. | 2,048 |
| AS198031 | Trustica s.r.o. | 2,048 |
| AS204165 | Cznet s.r.o. | 2,048 |
| AS48451 | Prazska energetika, a.s. | 2,048 |
| AS57566 | Wircom s.r.o. | 2,048 |
| AS196873 | Netlancers s.r.o. | 2,048 |
| AS198248 | Richard Filip | 2,048 |
| AS199657 | TNtech, s.r.o. | 2,048 |
| AS198282 | Cable-NET s.r.o. | 2,048 |
| AS56624 | Rtyne.net s.r.o. | 2,048 |
| AS57288 | StaMPi, spol. s r.o. | 2,048 |
| AS44712 | eHAMnet, s.r.o. | 2,048 |
| AS61425 | Mlada fronta a.s. | 2,048 |
| AS56821 | KnVnet services s.r.o. | 2,048 |
| AS20609 | KAZA.cz s.r.o. | 2,048 |
| AS48780 | OLTELECOM JSC | 2,048 |
| AS47767 | Regionalni centrum Olomouc s.r.o. | 2,048 |
| AS197277 | State Institute for Drug Control | 2,048 |
| AS206420 | KABEL servis Praha spol. s r.o. | 2,048 |
| AS206429 | CORSAT s.r.o | 2,048 |
| AS196815 | LAN servis s.r.o. | 2,048 |
| AS50971 | JHComp s.r.o. | 2,048 |
| AS50975 | AVX Czech republic s.r.o | 2,048 |
| AS199101 | Nordic Telecom Regional s.r.o. | 2,048 |
| AS44500 | Vlasimnet s.r.o. | 2,048 |
| AS202756 | RFE/RL, Inc., organizacni slozka | 1,792 |
| AS200844 | STUDENT AGENCY k.s. | 1,792 |
| AS51134 | Development 777 s.r.o. | 1,792 |
| AS199803 | ComSource s.r.o. | 1,536 |
| AS58239 | hanspaul-city.net s.r.o. | 1,536 |
| AS197694 | Municipal Office of the City Prague | 1,536 |
| AS48091 | Kraj Vysocina | 1,536 |
| AS196653 | BEST-NET s.r.o. | 1,536 |
| AS200449 | Qrator Labs CZ s.r.o. | 1,536 |
| AS204007 | Kleissner Investments s.r.o. | 1,536 |
| AS200678 | ISP Alliance a.s. | 1,280 |
| AS49359 | Dmitry Kozhushko | 1,280 |
| AS204332 | TKC system s.r.o. | 1,280 |
| AS197920 | SKODA ICT s.r.o. | 1,280 |
| AS198725 | Ultimum Technologies a.s. | 1,280 |
| AS42726 | BusinessCom CZ spol. s r.o. | 1,280 |
| AS62159 | Happy Technik s.r.o. | 1,280 |
| AS51211 | PE Rulev Dmitriy Alexandrovich | 1,280 |
| AS49013 | Fusion Media, s.r.o. | 1,280 |
| AS206270 | ISP Alliance a.s. | 1,024 |
| AS48085 | DNIPRO-Techcenter Ltd | 1,024 |
| AS48602 | Connect plus s.r.o. | 1,024 |
| AS48889 | GLOBECORP a.s. | 1,024 |
| AS49095 | PRAHA12.com s.r.o. | 1,024 |
| AS49121 | Infinity Telecom, s.r.o. | 1,024 |
| AS49142 | HBO Europe s.r.o. | 1,024 |
| AS50067 | CESAL s.r.o. | 1,024 |
| AS49573 | JimmyNet s.r.o. | 1,024 |
| AS197412 | BT MEDIA INVEST s.r.o. | 1,024 |
| AS197444 | Vlastimil Drazsky | 1,024 |
| AS197575 | CHP Mediana-Servis | 1,024 |
| AS197786 | Telefonnyie seti Ltd. | 1,024 |
| AS62405 | Brouzdal, s.r.o. | 1,024 |
| AS197895 | ONYX engineering, spol. s r.o. | 1,024 |
| AS198101 | Kooperativa pojistovna, a.s., Vienna Insurance Group | 1,024 |
| AS62176 | EZE A.S. | 1,024 |
| AS198212 | "TeleNet Sayansk" LLC | 1,024 |
| AS198284 | Mesto Velka Bystrice | 1,024 |
| AS198346 | NETFORMS s.r.o. | 1,024 |
| AS62102 | Informacni sluzby energetika a.s. | 1,024 |
| AS198657 | GOLDWARE s.r.o. | 1,024 |
| AS198814 | ALPHA StylSoft, s.r.o. | 1,024 |
| AS61981 | Mach3net s.r.o. | 1,024 |
| AS199298 | Jan Stetina | 1,024 |
| AS199350 | Ministerstvo financi | 1,024 |
| AS199405 | Oslavany.NET | 1,024 |
| AS199490 | INTERCONNECT s.r.o. | 1,024 |
| AS199600 | Virtis s.r.o. | 1,024 |
| AS8646 | cloudinfrastack, s.r.o. | 1,024 |
| AS199711 | National Cyber and Information Security Agency | 1,024 |
| AS199722 | Sberbank CZ, a.s. | 1,024 |
| AS200155 | Technologicke centrum Pisek s.r.o. | 1,024 |
| AS200474 | CRFreeNet, z.s. | 1,024 |
| AS200600 | Seznam.cz datova centra, s.r.o. | 1,024 |
| AS200635 | pragmatel s.r.o. | 1,024 |
| AS61169 | Nej.cz s.r.o. | 1,024 |
| AS61110 | Sprava informacnich technologii mesta Plzne, p.o. | 1,024 |
| AS200828 | TERMS a.s. | 1,024 |
| AS200874 | Liberecky kraj | 1,024 |
| AS200985 | BOK*Net, z.s. | 1,024 |
| AS201116 | Vybezek.NET s.r.o. | 1,024 |
| AS201163 | Komercni banka, a.s. | 1,024 |
| AS60266 | Home Credit International a.s. | 1,024 |
| AS12984 | PilsFree, z. s. | 1,024 |
| AS201457 | Kooperativa pojistovna, a.s., Vienna Insurance Group | 1,024 |
| AS60086 | Valvera s.r.o. | 1,024 |
| AS201533 | United Networks SE | 1,024 |
| AS201559 | United Networks SE | 1,024 |
| AS201625 | United Networks SE | 1,024 |
| AS59984 | KLFREE NETWORKS, s.r.o. | 1,024 |
| AS201727 | Spolek bubakov.net | 1,024 |
| AS201926 | Futurenet ISP s.r.o. | 1,024 |
| AS59925 | Seonet Multimedia s.r.o. | 1,024 |
| AS59871 | Heureka Group a.s. | 1,024 |
| AS202551 | INERA.CZ s.r.o. | 1,024 |
| AS202556 | Spolek Krivonet | 1,024 |
| AS202605 | EMPECOM, s.r.o. | 1,024 |
| AS202657 | Pavel Jochim | 1,024 |
| AS202719 | Pranet s.r.o. | 1,024 |
| AS59664 | Opton s.r.o. | 1,024 |
| AS202774 | COMTEX s.r.o. | 1,024 |
| AS202872 | KME, spol. s r. o. | 1,024 |
| AS202874 | Zlinsky Kraj | 1,024 |
| AS202877 | VEJNET.CZ s.r.o. | 1,024 |
| AS202979 | NGA Services, spol. s r.o. | 1,024 |
| AS203328 | PVfree.net, z. s. | 1,024 |
| AS58220 | Tomas Budai | 1,024 |
| AS203365 | Optet network, s. r. o. | 1,024 |
| AS203376 | Mailkit s.r.o. | 1,024 |
| AS203385 | Pernix systems s.r.o. | 1,024 |
| AS203411 | FORTUNA GAME a.s. | 1,024 |
| AS203450 | LOGICPRIM s.r.o. | 1,024 |
| AS203488 | DaLuNET s.r.o. | 1,024 |
| AS203550 | i2net cz s.r.o. | 1,024 |
| AS57904 | Vevynet s.r.o. | 1,024 |
| AS57779 | ICTIS.CZ s.r.o. | 1,024 |
| AS204080 | Apelby Solutions s.r.o. | 1,024 |
| AS57707 | Greendata s.r.o. | 1,024 |
| AS204351 | NAM system, a.s. | 1,024 |
| AS204394 | Cortex, a.s. | 1,024 |
| AS204409 | Prestonet s.r.o. | 1,024 |
| AS57560 | XLNET s.r.o. | 1,024 |
| AS204567 | PCKBnet s.r.o. | 1,024 |
| AS204570 | Vratislav Kriz | 1,024 |
| AS204772 | Reditelstvi silnic a dalnic CR | 1,024 |
| AS204886 | Metropolitni sit Humpolec spol. s r.o. | 1,024 |
| AS204943 | NTV cable s.r.o. | 1,024 |
| AS205002 | CUBESOL, s.r.o. | 1,024 |
| AS205044 | Pro-Line comp s.r.o. | 1,024 |
| AS205234 | Brnenske komunikace a.s. | 1,024 |
| AS205300 | Sunfox s.r.o. | 1,024 |
| AS205345 | HoralNET s.r.o. | 1,024 |
| AS205400 | VIVO CONNECTION spol. s r.o. | 1,024 |
| AS205535 | Windyghoul s.r.o. | 1,024 |
| AS205619 | Jiri Chalabala | 1,024 |
| AS205863 | Stepan Pokorny | 1,024 |
| AS205968 | GeneralNet s.r.o. | 1,024 |
| AS206177 | SitePark s.r.o. | 1,024 |
| AS206212 | KCG spol. s.r.o. | 1,024 |
| AS206287 | LysaFree, z.s. | 1,024 |
| AS57081 | Scarfbot Technologies, s.r.o. | 1,024 |
| AS206344 | AUKRO s.r.o. | 1,024 |
| AS206414 | TechCenter s.r.o. | 1,024 |
| AS20643 | PilsFree servis, s.r.o. | 1,024 |
| AS206438 | MX-NET Telekomunikace s.r.o. | 1,024 |
| AS206566 | savana.cz s.r.o | 1,024 |
| AS206784 | Internet Praha Josefov s.r.o. | 1,024 |
| AS206951 | BMB-Green s.r.o. | 1,024 |
| AS207015 | Position s.r.o. | 1,024 |
| AS20708 | SKODA AUTO a.s. | 1,024 |
| AS207153 | Stream-iT, s.r.o. | 1,024 |
| AS57007 | NITEX ISP s.r.o. | 1,024 |
| AS56936 | Mbit City Ltd. | 1,024 |
| AS56827 | mirnet s.r.o. | 1,024 |
| AS12344 | CZECH IT CLUSTER, druzstvo | 1,024 |
| AS13199 | Jaroslav Doubrava | 1,024 |
| AS207886 | ECOMP spol s r.o. | 1,024 |
| AS208093 | Moravskoslezsky kraj | 1,024 |
| AS208329 | Ceska televize | 1,024 |
| AS208355 | TechKeeper s.r.o. | 1,024 |
| AS208414 | WEDOS Internet, a.s. | 1,024 |
| AS208466 | E.ON Telco, s.r.o. | 1,024 |
| AS208543 | Diovetech s.r.o. | 1,024 |
| AS208659 | INNC s.r.o. | 1,024 |
| AS208663 | Martin Pustka | 1,024 |
| AS208805 | POPE servis s.r.o. | 1,024 |
| AS56562 | Telecom Plus Company Ltd. | 1,024 |
| AS208847 | Martin Fryzl | 1,024 |
| AS209055 | W.A.G. PAYMENT SOLUTIONS, A.S. | 1,024 |
| AS209155 | Onehostplanet s.r.o. | 1,024 |
| AS209621 | DOBNET, z.s. | 1,024 |
| AS196916 | BusinessCom CZ spol. s r.o. | 1,024 |
| AS209834 | KAZA.cz s.r.o. | 1,024 |
| AS56344 | Viridium.cz s.r.o. | 1,024 |
| AS209947 | M-wifi internet s.r.o. | 1,024 |
| AS196952 | BEZVANET s.r.o. | 1,024 |
| AS212138 | Technicke site Brno, akciova spolecnost | 1,024 |
| AS196978 | Milos Tuma | 1,024 |
| AS51744 | Non-profit organization Jablonka.cz | 1,024 |
| AS213152 | Narodni bezpecnostni urad Czech Republic | 1,024 |
| AS25238 | MONETA Money Bank, a.s. | 1,024 |
| AS51424 | Jiri Sperl | 1,024 |
| AS29504 | Freenet Liberec, z.s. | 1,024 |
| AS31559 | Matrigo s.r.o. | 1,024 |
| AS51382 | COMANET NETWORK | 1,024 |
| AS51371 | Ashtarak-Elit Ltd. | 1,024 |
| AS51331 | SychrovNET s.r.o | 1,024 |
| AS34475 | Agrostroj Pelhrimov, a.s. | 1,024 |
| AS34596 | HVfree.net servis. s.r.o. | 1,024 |
| AS34819 | H17 Networks, s.r.o. | 1,024 |
| AS35096 | Alef Nula a.s. | 1,024 |
| AS35420 | Perspektiva Ltd. | 1,024 |
| AS39736 | ICT Support, s.r.o. | 1,024 |
| AS50980 | E3.cz, sro | 1,024 |
| AS41779 | LajsiNET s.r.o. | 1,024 |
| AS42269 | Foton Ltd | 1,024 |
| AS50784 | Intraweb servis s.r.o. | 1,024 |
| AS44770 | Savvy s.r.o. | 1,024 |
| AS44984 | Fortion Networks, s.r.o. | 1,024 |
| AS50415 | Ahosting a.s. | 1,024 |
| AS47749 | ORIFLAME SOFTWARE s.r.o. | 1,024 |
| AS208950 | Ezpada s.r.o | 768 |
| AS59888 | PE Grinkiv Nadia Oliksandrivna | 768 |
| AS206591 | Alza.cz a.s. | 768 |
| AS209135 | Flowmon Networks a.s. | 768 |
| AS207095 | FORTUNA GAME a.s. | 768 |
| AS205653 | Jumpshot s.r.o. | 768 |
| AS204949 | Ceskomoravske informacni systemy s.r.o. | 768 |
| AS57472 | JR-NET, s.r.o. | 768 |
| AS42174 | Sipcom Ltd. | 768 |
| AS50833 | FIBER TELECOM s.r.o. | 768 |
| AS200070 | CZ.NIC, z.s.p.o. | 768 |
| AS199220 | KrU Stredoceskeho kraje | 768 |
| AS203208 | Czech Telecommunication Office | 768 |
| AS206718 | RFE/RL, Inc., organizacni slozka | 768 |
| AS48098 | Valikov Yury Aleksandrovich | 768 |
| AS206712 | FELDSAM s.r.o. | 768 |
| AS56988 | Mobile & Television Communications LLC | 512 |
| AS20701 | CZ.NIC, z.s.p.o. | 512 |
| AS49510 | TCV Ltd | 512 |
| AS206908 | FORTUNA GAME a.s. | 512 |
| AS206785 | Magistrat mesta Brna | 512 |
| AS42995 | Firma Geotelecom Ltd. | 512 |
| AS206234 | FORTUNA GAME a.s. | 512 |
| AS196764 | RFI Minprirody Rossii FBGU | 512 |
| AS204668 | ASTANA Technologies s.r.o. | 512 |
| AS196687 | obcanske sdruzeni TRENET | 512 |
| AS202948 | FORTUNA GAME a.s. | 512 |
| AS59681 | Satellit PE | 512 |
| AS202131 | ISP Alliance a.s. | 512 |
| AS43866 | Altron a.s. | 512 |
| AS201934 | Satan s.r.o. | 512 |
| AS201931 | LBnet.cz s.r.o. | 512 |
| AS201811 | Austole s.r.o. | 512 |
| AS201608 | UnArtel s.r.o. | 512 |
| AS60275 | RVTech s.r.o. | 512 |
| AS200806 | BOHEMIA ENERGY entity s.r.o. | 512 |
| AS61416 | STATE AUTONOMOUS ESTABLISHMENT OF THE ARKHANGELSK REGION MANAGEMENT OF INFORMATION AND COMMUNICATION TECHNOLOGY OF ARKHANGELSK REGION | 512 |
| AS198621 | AVAST Software s.r.o. | 512 |
| AS49506 | GumsNet Ltd | 512 |
| AS62083 | Fio banka, a.s. | 512 |
| AS49313 | Seva-Host Ltd | 512 |
| AS198143 | Ceska Posta s.p. | 512 |
| AS48131 | i-registry s.r.o. | 512 |
| AS198103 | CCS Ceska spolecnost pro platebni karty s.r.o. | 512 |
| AS197698 | D-H-T SYSTEMS s.r.o. | 512 |
| AS50695 | VLTAVA LABE MEDIA a.s. | 512 |
| AS197353 | NN Management Services, s.r.o. | 512 |
| AS51245 | Center of Information Technologies Ltd. | 512 |
| AS30928 | ZAO Rubtsovsk | 512 |
| AS30738 | NetArt Group s.r.o. | 512 |
| AS51448 | Uralskie Kabelnye Seti Ltd. | 512 |
| AS51521 | Resident Control s.r.o. | 512 |
| AS25553 | TRK Gluhov Ltd. | 512 |
| AS197144 | PP SVS Stream | 512 |
| AS25093 | Ceska sporitelna a.s. | 512 |
| AS25321 | GROUP 4 Secure Solutions a.s. | 512 |
| AS51727 | SKODA POWER s.r.o. | 512 |
| AS212569 | Yung Wo Tin Leung | 512 |
| AS39896 | FIBER TELECOM s.r.o. | 512 |
| AS212453 | FORTUNA GAME a.s. | 512 |
| AS212325 | ADC Systems s.r.o. | 512 |
| AS21205 | ING WholeSale Bank | 512 |
| AS196943 | Vissado s.r.o. | 512 |
| AS210061 | Ladislav Kepl | 512 |
| AS209795 | SPC-net s.r.o. | 512 |
| AS41359 | Telefonzentrale s.r.o. | 512 |
| AS208712 | CENDIS, s.p. | 512 |
| AS208422 | Infinity Telecom, s.r.o. | 512 |
| AS208060 | Dr. Max BDC, s.r.o. | 512 |
| AS49997 | Piton Ltd | 512 |
| AS49580 | Monet +, a.s. | 512 |
| AS56717 | OG Soft s.r.o. | 256 |
| AS12608 | NTX Technologies s.r.o. | 256 |
| AS15380 | Air Navigation Services of the Czech Republic, state enterprise | 256 |
| AS15731 | Reliable Communications s.r.o. | 256 |
| AS15741 | Expiline Ltd. | 256 |
| AS196762 | ALKOM Security, a.s. | 256 |
| AS196849 | Marcela Byrtusova | 256 |
| AS197566 | OK-NET s.r.o. | 256 |
| AS197875 | UNIPETROL RPA, s.r.o. | 256 |
| AS198494 | PREGIS, a.s | 256 |
| AS199059 | Maurice Ward & Co., s.r.o. | 256 |
| AS199604 | OLOMOUCKY KRAJ | 256 |
| AS199665 | Hana Juzkova | 256 |
| AS199806 | DCIT, a.s. | 256 |
| AS200646 | BH securities, a.s. | 256 |
| AS201263 | Brno University of Technology | 256 |
| AS201594 | Czech Telecommunication Office | 256 |
| AS201922 | amccomp s.r.o. | 256 |
| AS202073 | Itego a.s. | 256 |
| AS202084 | Penta Investments, s.r.o. | 256 |
| AS203299 | Ivo Hazmuk | 256 |
| AS204113 | Security Information Service | 256 |
| AS204543 | Filip Hruska | 256 |
| AS205724 | T.S.BOHEMIA a.s. | 256 |
| AS205982 | Mraknet s.r.o. | 256 |
| AS206468 | Treboradice.net z.s. | 256 |
| AS206613 | Tipsport.net a.s. | 256 |
| AS206683 | Moravskoslezske inovacni centrum Ostrava, a.s. | 256 |
| AS206703 | Netcom Solutions s.r.o. | 256 |
| AS207231 | FuturNET, s.r.o. | 256 |
| AS207850 | HovNet-SERVIS s.r.o. | 256 |
| AS208143 | amccomp s.r.o. | 256 |
| AS208259 | SamaTech | 256 |
| AS209680 | JetBrains, s. r. o. | 256 |
| AS211594 | Peernet s.r.o. | 256 |
| AS211700 | Dexus Internet s.r.o. | 256 |
| AS212362 | KMK systems s.r.o. | 256 |
| AS212906 | Moneroj s.r.o. | 256 |
| AS213387 | TeSuNet s.r.o. | 256 |
| AS213395 | NetX Networks a.s. | 256 |
| AS28892 | Cesky urad zememericky a katastralni | 256 |
| AS3229 | Intek Ltd. | 256 |
| AS34293 | J.S.tel s.r.o. | 256 |
| AS34487 | SouthPrague.Net, z.s. | 256 |
| AS39453 | KSRZIS | 256 |
| AS41180 | RFE/RL, Inc., organizacni slozka | 256 |
| AS43234 | Chip-Telecom Ltd. | 256 |
| AS44104 | LCJ s.r.o. | 256 |
| AS48405 | CGI IT Czech Republic s.r.o. | 256 |
| AS48802 | OOO "Povolzhskiy Processingoviy Center" | 256 |
| AS48890 | SOLVO ltd | 256 |
| AS49262 | Ataccama Software, s.r.o. | 256 |
| AS50097 | IPVOIP s.r.o. | 256 |
| AS50103 | Media Region Inc. | 256 |
| AS50248 | Vladivostok international airport JSC | 256 |
| AS50356 | Camelot Ltd | 256 |
| AS51278 | Webglobe, s.r.o. | 256 |
| AS51449 | Kabelova televize Usti nad Orlici, spol. s r. o. | 256 |
| AS51463 | FAJNCOM s.r.o. | 256 |
| AS51884 | Tera Telecom Ltd | 256 |
| AS56508 | Regionecoproduct-Povolzhie Ltd. | 256 |
| AS56891 | Ceskomoravska zarucni a rozvojova banka, a.s. | 256 |
| AS57572 | Lesta Ltd. | 256 |
| AS59552 | VHG Ltd | 256 |
| AS59826 | PE Oleynik Dmitro Oleksandrovich | 256 |
| AS60218 | IT8 - Informacni technologie s.r.o. | 256 |
| AS60724 | Sicuro Services s. r. o. | 256 |
| AS61123 | Ekoniva-Tehnika Ltd. | 256 |
| AS61166 | Russian Federal Service for Alcohol Market Regulation | 256 |
| AS62298 | Computer Systems Consulting s.r.o. | 256 |
| AS9053 | VSHosting s.r.o. | 256 |
| AS42477 | Cerberos s.r.o. | 0 |
| AS42422 | SecurityNet.cz s.r.o. | 0 |
| AS41824 | O2 Czech Republic, a.s. | 0 |
| AS41711 | FreeTel, s.r.o. | 0 |
| AS51025 | VSHosting s.r.o. | 0 |
| AS41456 | KP NETWORK, spol. s r.o. | 0 |
| AS41267 | GREPA Networks s.r.o. | 0 |
| AS40964 | ASTELNET s.r.o. | 0 |
| AS39050 | NET service solution, s.r.o. | 0 |
| AS34371 | Metropolitni s.r.o. | 0 |
| AS34302 | Sprintel s.r.o. | 0 |
| AS198171 | Webglobe, s.r.o. | 0 |
| AS34070 | DATin internet s.r.o. | 0 |
| AS51351 | LTD Objedinennaja Setevaja Kompanija | 0 |
| AS33877 | Druzstvo OFX | 0 |
| AS3234 | Parliament of the Czech Republic | 0 |
| AS29525 | Virtualmaster, s.r.o. | 0 |
| AS29401 | SH.cz s.r.o. | 0 |
| AS29113 | Vodafone Czech Republic a.s. | 0 |
| AS28904 | PODA a.s. | 0 |
| AS28755 | ha-vel internet s.r.o. | 0 |
| AS198027 | VITKOVICE IT SOLUTIONS a.s. | 0 |
| AS15485 | T-Mobile Czech Republic a.s. | 0 |
| AS2819 | T-Mobile Czech Republic a.s. | 0 |
| AS2605 | CESNET z.s.p.o. | 0 |
| AS25036 | O2 Czech Republic, a.s. | 0 |
| AS24828 | Vodafone Czech Republic a.s. | 0 |
| AS21435 | Vodafone Czech Republic a.s. | 0 |
| AS213359 | Jan Korinek | 0 |
| AS213104 | FIBER TELECOM s.r.o. | 0 |
| AS213019 | Blast Group Inc. | 0 |
| AS51801 | Nano.cz s.r.o. | 0 |
| AS197815 | AVAST Software s.r.o. | 0 |
| AS212876 | Pardubicky Kraj | 0 |
| AS51902 | Web4Soft Internet s.r.o. | 0 |
| AS212224 | Coolhousing s.r.o. | 0 |
| AS211898 | vpsFree.cz, z.s. | 0 |
| AS211731 | Ministry of labour and social affairs | 0 |
| AS211489 | Modralog S.r.o | 0 |
| AS21142 | T-Mobile Czech Republic a.s. | 0 |
| AS52095 | Netassist International s.r.o. | 0 |
| AS21082 | Reliable Communications s.r.o. | 0 |
| AS210325 | Air Networks s.r.o. | 0 |
| AS210169 | InloopX s.r.o. | 0 |
| AS210115 | Artemis Hosting s.r.o. | 0 |
| AS5407 | PODA a.s. | 0 |
| AS210111 | Netcraft Solutions s.r.o. | 0 |
| AS210088 | KONTRAX FT, s.r.o. | 0 |
| AS209840 | S1 Communications s.r.o. | 0 |
| AS209823 | Alphatech Resource Holdings s.r.o. | 0 |
| AS209816 | Trend Digital Marketing s.r.o. | 0 |
| AS209692 | FOXCONN CZ s.r.o. | 0 |
| AS209477 | MAXICOM HOLDING a.s. | 0 |
| AS197376 | DataSpring s.r.o. | 0 |
| AS208836 | INTERCONNECT SM LLC | 0 |
| AS208387 | Blond & Brown s.r.o. | 0 |
| AS207855 | ModernTV Anycast | 0 |
| AS207696 | Dopravni podnik hl.m. Prahy, a.s. | 0 |
| AS207643 | BT MEDIA INVEST s.r.o. | 0 |
| AS207632 | Jan Betik | 0 |
| AS6706 | Dial Telecom, a.s. | 0 |
| AS207583 | Technologicke centrum a.s. | 0 |
| AS207576 | KOVO - PLAZMA s.r.o. | 0 |
| AS207575 | Zahradnicke centrum Brabec, s.r.o. | 0 |
| AS207354 | Teleconnect CZ s.r.o. | 0 |
| AS206569 | TEORA s.r.o. | 0 |
| AS206463 | Pavel Zizka | 0 |
| AS206334 | AVAST Software s.r.o. | 0 |
| AS57158 | GRAPE SC, a.s. | 0 |
| AS206321 | STARTECH spol. s r.o. | 0 |
| AS57194 | CHP Koshelnik Sergey Valentinovich | 0 |
| AS206050 | FreeNetwork s.r.o. | 0 |
| AS205719 | Data & File Processing s.r.o. | 0 |
| AS205549 | FixPro,z.s. | 0 |
| AS205248 | Netassist International s.r.o. | 0 |
| AS204907 | Air Bank a.s. | 0 |
| AS204746 | Komplet NET s.r.o. | 0 |
| AS204666 | Jiri Tlapak | 0 |
| AS57523 | AMEuroTel s.r.o. | 0 |
| AS57540 | Nordic Telecom Regional s.r.o. | 0 |
| AS204505 | IT & WP HOST s.r.o. | 0 |
| AS204405 | Durnet.cz sro | 0 |
| AS204375 | SychrovNET s.r.o | 0 |
| AS197299 | CENTEL s.r.o. | 0 |
| AS204247 | Cznet s.r.o. | 0 |
| AS204216 | netsearch s.r.o. | 0 |
| AS204214 | S.I.C. spol. s r.o. | 0 |
| AS204058 | Wawahi s.r.o. | 0 |
| AS204051 | FLEA s.r.o. | 0 |
| AS203743 | ISP Alliance a.s. | 0 |
| AS203705 | Pavel Zizka | 0 |
| AS57825 | MoravanyNET s.r.o. | 0 |
| AS203645 | Jan Ryznar | 0 |
| AS57919 | Wicom Ltd. | 0 |
| AS203342 | Ladislav Rudolf | 0 |
| AS203072 | DomaTV s.r.o. | 0 |
| AS202888 | KETNET s.r.o. | 0 |
| AS197246 | Glow Internet s.r.o. | 0 |
| AS202733 | OK COMP s.r.o. | 0 |
| AS202732 | Ing Petr Sramek | 0 |
| AS197059 | HOTNET s.r.o. | 0 |
| AS202522 | Nordic Telecom Regional s.r.o. | 0 |
| AS202066 | Nas NET s.r.o. | 0 |
| AS201987 | HEXAGEEK s.r.o. | 0 |
| AS59932 | Quick Technology Company s.r.o. | 0 |
| AS201761 | ISP Alliance a.s. | 0 |
| AS59969 | FOP Kameristov Andrey Evgenovuch | 0 |
| AS201732 | Maxicom Technologies s.r.o. | 0 |
| AS201671 | Emerald Real Group s.r.o. | 0 |
| AS201464 | ISP Alliance a.s. | 0 |
| AS60143 | Brno University of Technology | 0 |
| AS60208 | J&T BANKA, a.s. | 0 |
| AS197026 | Galevi s.r.o. | 0 |
| AS201228 | Czech metrology institute | 0 |
| AS201187 | Whois protection, this company does not own this domain name s.r.o. | 0 |
| AS201179 | Vaudevile s.r.o. | 0 |
| AS201007 | Tesco Stores CR a.s. | 0 |
| AS60606 | PRO-ZETA a.s. | 0 |
| AS60647 | Prazska plynarenska,a.s. | 0 |
| AS15512 | Vodafone Czech Republic a.s. | 0 |
| AS60727 | K2 atmitec s.r.o. | 0 |
| AS200809 | ASJA CZ s.r.o. | 0 |
| AS200717 | STEN.cz s.r.o. | 0 |
| AS8747 | Dial Telecom, a.s. | 0 |
| AS15494 | BT Limited, organizacni slozka | 0 |
| AS200673 | AMARTI s.r.o. | 0 |
| AS61195 | Peering.cz s.r.o. | 0 |
| AS200633 | CHISTOV PRAGA s.r.o. | 0 |
| AS200393 | ELAN plus, s.r.o. | 0 |
| AS199630 | Municipal Office of the City Prague | 0 |
| AS61973 | Netassist International s.r.o. | 0 |
| AS198953 | PricewaterhouseCoopers IT Services, s.r.o. | 0 |
| AS198882 | Karlovarsky Kraj | 0 |
| AS50015 | Oleksandr Butenko | 0 |
| AS49972 | IT ADMIRABLE SERVICE LTD | 0 |
| AS49418 | Domashnie Seti Ltd | 0 |
| AS198564 | STARNET, s.r.o. | 0 |
| AS198510 | Krajska zdravotni, a.s. | 0 |
| AS49334 | Sergey Krashevich | 0 |
| AS48268 | Inter Fiber s.r.o. | 0 |
| AS47924 | Grigory Aleksandrovich Shushpanov | 0 |
| AS198420 | Nordic Telecom s.r.o | 0 |
| AS47913 | Cerberos s.r.o. | 0 |
| AS47681 | Nej.cz s.r.o. | 0 |
| AS198250 | ELDATA prazska s.r.o. | 0 |
| AS47627 | NIX.CZ z.s.p.o. | 0 |
| AS47200 | NIX.CZ z.s.p.o. | 0 |
| AS50491 | Planet A, a.s. | 0 |
| AS47122 | inet4 s.r.o. | 0 |
| AS44910 | FH Miraj-94 | 0 |
| AS44672 | OncaOnca Ltd. | 0 |
| AS43130 | NKL LLC | 0 |
Details
Autonomous System Numbers (ASNs) are assigned to entities such as Internet Service Providers and other large organizations that control blocks of IP addresses. This network page, and the organization field that's shown on the main IP address information page and also returned in the geolocation API are based on the ASN.
This page shows ASNs for Czech Republic. See the global ASN report for network, IP address information and whois details for other countries.