Internet Assigned Numbers Authority

Autonomous System (AS) Numbers

Last Updated
2024-04-10
Note
Autonomous System (AS) Numbers are used by various routing protocols. IANA allocates 
AS Numbers to Regional Internet Registries (RIRs). The RIRs further allocate or assign AS 
Numbers to network operators in line with RIR policies. The [five RIRs] are:

- [AFRINIC]
- [APNIC]
- [ARIN]
- [LACNIC]
- [RIPE_NCC]

AS Numbers can be obtained from the registry in your region.
Available Formats

XML

HTML

Plain text

Registries included below

16-bit Autonomous System Numbers

Registration Procedure(s)
RIR request to the IANA or IETF Review. Allocated following the Global Policy published at   
[http://www.icann.org/en/resources/policy/global-addressing].
Reference
[RFC1930][RFC5398][RFC6996][RFC7249]
Available Formats

CSV
Number Description WHOIS RDAP Reference Registration Date
0 Reserved [RFC7607]
1-1876 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
1877-1901 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/
1902-2042 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2043 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/
2044-2046 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2047 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/
2048-2106 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2107-2136 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/
2137-2584 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2585-2614 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/
2615-2772 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2773-2822 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/
2823-2829 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2830-2879 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/
2880-3153 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
3154-3353 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/
3354-4607 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
4608-4865 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/
4866-5376 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
5377-5631 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/
5632-6655 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
6656-6911 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/
6912-7466 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
7467-7722 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/
7723-8191 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
8192-9215 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/
9216-10239 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/
10240-12287 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
12288-13311 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/
13312-15359 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
15360-16383 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/
16384-17407 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
17408-18431 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/
18432-20479 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
20480-21503 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/
21504-23455 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
23456 AS_TRANS [RFC6793]
23457-23551 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
23552-24575 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/
24576-25599 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/
25600-26623 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2002-03
26624-27647 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2002-09
27648-28671 Assigned by LACNIC whois.lacnic.net https://rdap.lacnic.net/rdap/ 2002-11
28672-29695 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2002-12
29696-30719 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2003-03
30720-31743 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2003-09
31744-32767 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2003-11
32768-33791 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2004-05
33792-34815 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2004-06
34816-35839 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2005-02
35840-36863 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2005-02
36864-37887 Assigned by AFRINIC whois.afrinic.net https://rdap.afrinic.net/rdap/
http://rdap.afrinic.net/rdap/
2005-04
37888-38911 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2005-06
38912-39935 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2005-09
39936-40959 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2006-03-29
40960-41983 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2006-04-13
41984-43007 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2006-11-17
43008-44031 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2007-04-23
44032-45055 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2007-09-14
45056-46079 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2007-10-11
46080-47103 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2008-03-27
47104-48127 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2008-04-07
48128-49151 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2008-09-09
49152-50175 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2009-03-06
50176-51199 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2009-03-06
51200-52223 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2009-03-06
52224-53247 Assigned by LACNIC whois.lacnic.net https://rdap.lacnic.net/rdap/ 2009-03-11
53248-54271 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2009-04-21
54272-55295 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2009-04-21
55296-56319 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2009-09-02
56320-57343 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2011-01-04
57344-58367 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2011-01-04
58368-59391 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2011-08-09
59392-60415 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2012-03-21
60416-61439 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2012-03-21
61440-61951 Assigned by LACNIC whois.lacnic.net https://rdap.lacnic.net/rdap/ 2013-06-11
61952-62463 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2013-09-09
62464-63487 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2013-05-30
63488-63999 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2013-09-11
64000-64098 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2014-09-02
64099-64197 Assigned by LACNIC whois.lacnic.net https://rdap.lacnic.net/rdap/ 2014-09-05
64198-64296 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2015-04-29
64297-64395 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2016-05-25
64396-64495 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2016-07-29
64496-64511 Reserved for use in documentation and sample code [RFC5398] 2008-12-03
64512-65534 Reserved for Private Use [RFC6996]
65535 Reserved [RFC7300]

32-bit Autonomous System Numbers

Registration Procedure(s)
RIR request to the IANA or IETF Review. Allocated following the Global Policy published at   
[http://www.icann.org/en/resources/policy/global-addressing].
Reference
[RFC1930][RFC5398][RFC6793][RFC6996][RFC7249]
Available Formats

CSV
Number Description WHOIS RDAP Reference Registration Date
0-65535 See Sub-registry 16-bit AS numbers [RFC1930]
65536-65551 Reserved for use in documentation and sample code [RFC5398] 2008-12-03
65552-131071 Reserved
131072-132095 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2006-11-29
132096-133119 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2011-08-09
133120-133631 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2013-09-11
133632-134556 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2014-09-02
134557-135580 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2014-09-02
135581-136505 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2016-05-25
136506-137529 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2016-05-25
137530-138553 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2017-12-07
138554-139577 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2017-12-07
139578-140601 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2019-06-12
140602-141625 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2019-06-12
141626-142649 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2020-10-20
142650-143673 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2020-10-20
143674-144697 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2021-05-05
144698-145721 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2021-05-05
145722-146745 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2021-05-05
146746-147769 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2021-05-05
147770-148793 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2021-10-11
148794-149817 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2021-10-11
149818-150841 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2021-10-11
150842-151865 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2021-10-11
151866-152889 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2023-05-10
152890-153913 Assigned by APNIC whois.apnic.net https://rdap.apnic.net/ 2023-05-10
153914-196607 Unallocated
196608-197631 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2006-11-29
197632-198655 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2011-01-04
198656-199679 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2012-03-21
199680-200191 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2013-09-09
200192-201215 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2014-02-28
201216-202239 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2014-02-28
202240-203263 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2015-06-11
203264-204287 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2015-06-11
204288-205211 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2016-07-29
205212-206235 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2016-07-29
206236-207259 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2016-07-29
207260-208283 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2018-08-20
208284-209307 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2018-08-20
209308-210331 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2018-08-20
210332-211355 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2020-04-01
211356-212379 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2020-04-01
212380-213403 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2020-04-01
213404-214427 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2023-08-10
214428-215451 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2023-08-10
215452-216475 Assigned by RIPE NCC whois.ripe.net https://rdap.db.ripe.net/ 2023-08-10
216476-262143 Unallocated
262144-263167 Assigned by LACNIC whois.lacnic.net https://rdap.lacnic.net/rdap/ 2006-11-29
263168-263679 Assigned by LACNIC whois.lacnic.net https://rdap.lacnic.net/rdap/ 2013-06-11
263680-264604 Assigned by LACNIC whois.lacnic.net https://rdap.lacnic.net/rdap/ 2014-09-05
264605-265628 Assigned by LACNIC whois.lacnic.net https://rdap.lacnic.net/rdap/ 2014-09-05
265629-266652 Assigned by LACNIC whois.lacnic.net https://rdap.lacnic.net/rdap/ 2016-09-08
266653-267676 Assigned by LACNIC whois.lacnic.net https://rdap.lacnic.net/rdap/ 2017-07-21
267677-268700 Assigned by LACNIC whois.lacnic.net https://rdap.lacnic.net/rdap/ 2017-07-21
268701-269724 Assigned by LACNIC whois.lacnic.net https://rdap.lacnic.net/rdap/ 2018-12-07
269725-270748 Assigned by LACNIC whois.lacnic.net https://rdap.lacnic.net/rdap/ 2018-12-07
270749-271772 Assigned by LACNIC whois.lacnic.net https://rdap.lacnic.net/rdap/ 2020-05-18
271773-272796 Assigned by LACNIC whois.lacnic.net https://rdap.lacnic.net/rdap/ 2020-05-18
272797-273820 Assigned by LACNIC whois.lacnic.net https://rdap.lacnic.net/rdap/ 2021-12-07
273821-274844 Assigned by LACNIC whois.lacnic.net https://rdap.lacnic.net/rdap/ 2024-03-22
274845-327679 Unallocated
327680-328703 Assigned by AFRINIC whois.afrinic.net https://rdap.afrinic.net/rdap/
http://rdap.afrinic.net/rdap/
2006-11-29
328704-329727 Assigned by AFRINIC whois.afrinic.net https://rdap.afrinic.net/rdap/
http://rdap.afrinic.net/rdap/
2020-03-05
329728-393215 Unallocated
393216-394239 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2006-11-30
394240-395164 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2015-04-29
395165-396188 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2016-05-03
396189-397212 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2016-05-03
397213-398236 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2018-08-09
398237-399260 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2018-08-09
399261-400284 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2020-11-02
400285-401308 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2020-11-02
401309-402332 Assigned by ARIN whois.arin.net https://rdap.arin.net/registry
http://rdap.arin.net/registry
2024-04-10
402333-4199999999 Unallocated
4200000000-4294967294 Reserved for Private Use [RFC6996]
4294967295 Reserved [RFC7300]

Contact Information

ID Name Contact URI Last Updated
[AFRINIC] AFRINIC mailto:hostmaster&afrinic.net 2013-09-09
[APNIC] APNIC mailto:helpdesk&apnic.net 2013-09-09
[ARIN] ARIN mailto:hostmaster&arin.net 2013-09-09
[LACNIC] LACNIC mailto:hostmaster&lacnic.net 2013-09-09
[RIPE_NCC] RIPE NCC mailto:ncc&ripe.net 2013-09-09